# If You Have a Cyclone Dust Collector...



## DavidNJ (Dec 10, 2012)

Could you share some information?

Which model you have?

Why you chose that brand and model?

What brands and models did you reject and why?

How does the ducting run/work in your shop? Multiple tools with blast gates? A flexible hose to a single tool at a time?

What dust collector did you have prior to your cyclone dust collector?

Are you satisfied with your dust collector?

If you'd like to also post a picture of your installation, that would be great.

I'm primarily interested in the dust collectors 2.5hp and under, but would be interested in all input.

Thanks,

David


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## kizerpea (Dec 2, 2011)

Well my friend this is a can of worms busted…the frist answer of many i,m sure..build my own…in my projects..
As many guys here did ..bang for the buck…harbor freight 2hp is the way to go …an build from there..


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## wapakfred (Jul 29, 2011)

My current one is an Oneida, I bought it one day when I went brain dead. I'm hoping to replace it with a CV. But it replaced a shop built one (Wood magazine design) that was powered by a PSI 2.5HP SS DC. My duct was 4" PVC at first, and i quickly upsized that to 6" PVC. The 6" runs as close to every tool possible, and each tool has a gate. My current DC moves a lot of air, and to be honest everything is fine in terms of capturing the dust. Where my Oneida falls short is in separating the dust before the air gets to the filter. It's so bad I have a gauge on the discharge to measure the filter 's air flow. The Oneida is built like a tank, but it skips the finer points of what Pentz proved to be good for separation. No squared/sloping inlet, a neutral vane that's improperly designed (IMHO), no air ramp…all of which get the last drop of fine dust from the airstream. Mine started life as a 2HP unit, and I upsized the motor to 5HP (another long story).


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## Grandpa (Jan 28, 2011)

I bought a Clear Vue 5 hp. It really wasn't that much higher than a 3 hp made by other companies. It had the Pentz endorsement and the customer service was great. It came with a remote control. I used 6 inche spiral wrap metal pipe. As I got closer to a tool I reduced it to 5 inch metal then 4 inch metal. Each tool is connected all the time with a blast gate in place. My shop is 30×40 ft so I installed the collector in the center end and ran a trunk line down the center of the room with branches to the machines. I used wyes and 45 deg elbows. 
I was in Grizzly one day in Springfield, MO. I was looking at dust collectors. Another customer came by and said buy the larger of the collectors. I didn'[t do that the first time but I did when that unit was too small. He walked on by. I thought about that statement for 2 years before I made a decision. If I went to the 3 hp Grizzly I would have something that would do the job I needed done. Then I looked at the price and decided I could have a larger unit if I wanted to spend about $200 more. I chose to do that. I considered buy the Harbor Freight and upgrading with the better fileter system etc. By the time you do those things you can go buy a good system that is already together. Just bite the bullet and do it. You will spend it anyway.


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## Dal300 (Aug 4, 2011)

I opted for the 1hp Harbor Freight dust collector. It's not powerful, but I set it up with 4" green PVC and 90° elbows.
The longest run is from the band saw with a 2" PVC (sched 40) to a 4" bushing to the rest of the system.
It's about 6' total from tool to dust bag.

I haven't hooked the table saw up to it yet, although that is in the works, but I do have a clean up opening that I can use to sweep all the floor FOD into. Every drop is removable and I have a short piece of pipe with a cap over it to remove each piece from the system. It may not be as fast and pretty or elegant as having blast gates or 5HP, but so far it works for me.

I modified the output so that it emptied into a 42 gallon Rubbermaid garbage can with a contractor bag in it.
The output from there is just a straight up run of 4" with the bag over it.

I also have it hooked to the planer and it catches probably 95% or more of the chips and shavings and dust with no problem…. at least until the garbage can starts to fill. I am full at about the 35 gallon mark.

Eventually I'll rebuild the system, make it a bit more efficient, but for right now it works fine for what I'm doing.


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## DavidNJ (Dec 10, 2012)

Fred, which model Oneida do you have? Oneida has at least two designs. One is a cone its entire length, the other has a more conventional design.


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## SASmith (Mar 22, 2010)

I am like kizerpea. I have a shop made wooden cyclone on a 2HP HF DC.


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## Manitario (Jul 4, 2010)

I have the Clearvue 5hp cyclone; I love it and I am completely satisfied with it, however, it is expensive. From what I've read and the specs online some of the higher HP Penn State Ind. "Tempest" units are almost equivalent but cheaper. I have 6" ducting for my main lines in my shop and short runs of flex for the drop down; and run only one blast gate open at a time. It lives in an insulated closet I built for it in a corner of the shop because it is loud!!


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## wapakfred (Jul 29, 2011)

David, mine is the Super Dust Gorilla.


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## DavidNJ (Dec 10, 2012)

Fred, what did Oneida say about your problem. There units are generally considered good. The Super Gorilla has a conventional cyclone. While the tuning tricks are niceties, it should still work pretty well. I'm wondering if it is too strong. Have you tried opening two gates instead of just one one on the machine you are using?

Rob, nice shop, I'm jealous. How do you like your SawStop?

Scott…I'm impressed and curious about the wood cyclone. There is no reason it should work. But does it? How do you connect it in your shop? The issue is pressure drop across the cyclone in conjunction with the capability of your motor/impeller vs. the load from your shop. What is the load on the dust collector in your shop?

The cyclone is a first stage that enables a second stage for fine filtration. However, in the picture you still had a bag on the HF. Have you considered a canister or MERV 15 nano canister?


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## Manitario (Jul 4, 2010)

Thanks David! I like the Sawstop; safety features aside, it is the nicest TS that I've ever owned.


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## wapakfred (Jul 29, 2011)

David, to make the story as short as possible, I spent hours talking/emailing to Oneida winding up with Bill Witter (the founder, I think). After providing them with samples of the dust in my filter, a layout of the system, and a considerable amount of other info, I never heard another word from them! My unit is separating 98.4% of the debris by volume. Oneida specs say 99%, so I'm essentially getting what they designed. Here's my beef: that isn't good enough, and the Pentz design changes get most of that last 1% (and make the unit 2-3 times as expensive). But if you use a lot of fine dust producing tools (drum sander, for example) you really need that last 1% of separation. Otherwise you wind up cleaning your filter twice per 35 gallon drum of chips. One more thought: that stuff that would make it more expensive is what Grizzly somehow figured out a way to incorporate without a stratospheric price….so I guess it can be done.


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## DavidNJ (Dec 10, 2012)

Fred…your Dust Gorilla should be a fine duct collector. Oneida's MERV16+ HEPA filters are probably the best offered to the hobbyist. ClearVue, Wynn, and Penn State mark their nano-filters as MERV 15.

My hypothesis is that you have too much power in your DC. If all the blast gates are closed it is trying to satisfy itself though the air openings in the one tool you are using. That may be creating very high vacuum in the system, enough that it is vacuuming the cyclone and its bin. Remember, the cyclone is basically just an empty chamber.

If that hypothesis is correct, opening some of your other blast gates for machines not in use should fix the problem, although probably at an increase in noise level. If it works, a long term solution may be a new duct port near the cyclone with a blast gate and automotive air filter. That would allow you to regulate the vacuum level.

Further justification for this hypothesis is Oneida's creation of Smart dust collectors that monitor some combination of vacuum level and air flow/air velocity and adjust the compressor accordingly. In our shops we have tools that may vary by a factor of 2x or 3x in air flow needs for dust collection and often size the DC to handle the largest with a buffer for error and expansion.

It's worth 30 minutes to run the test, isn't it?


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## mbs (May 8, 2010)

I started with at PSI tempest that would suck up a pc of paper. Went with a Clearview and love it. Look at "my workshop" where I have some pics, listed things I would do the same and things I would do differently. I also made a thien separator for my garage shop with a 2 hp jet brand and wynn filter.

To answer your question better we need to know more about your intent, configuration and shop tools.


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## mbs (May 8, 2010)

David,

I read your responses to what others have written. You seem to know a lot about dust collection already. just curious, why are you asking us the questions?


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## DavidNJ (Dec 10, 2012)

If you follow my one week old thread you will see a week ago I didn't know much. I still have lots of questions.

In the earlier thread the group discussion was more along the lines of: do you need a canister? Is a nanofilter excessive? Do you need a cyclone? Isn't a cyclone overkill? Commercial shops don't use cyclones, so why should a home shop need one?

I think I have a handle on that: http://lumberjocks.com/replies/553445

In this thread I'm trying to understand real world experiences with cyclone systems. Two ClearVue systems, one Dust Gorilla, and a homebuilt wooden cyclone. An impressive group although I'm hoping for more: different size systems, Grizzlys, Penn State Tempests, etc.

mbs, why did you replace the PSI with the ClearVue? Is it outside your workshop. That is an impressive workshop: 2 Delta TS (are they on the same rails?), a large sliding table saw, an Incra router table (why no Incra fence on the Deltas), a large blue thing in the middle I don't recognize. Is it an obelisque from 2001, A Space Odyssey?

I didn't know there was a place in AZ that had grass and trees like that.


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## mbs (May 8, 2010)

David,

I welded up a nice mobile cart for the tempest, hooked up and tested it with just a 6' long hose, 4" or 5" Dia. It performed pathetically! I didn't even spend time hooking it up to ducting. I sold it for a loss because I had purchased it a few years earlier and never hooked it up so it was out of warranty. PSI has redesigned the tempest since I bought mine and I can't comment on the quality or performance of the newer design. Other items I've purchased from PSI have been the same quality that Harbor Freight sells.

The clearview is outside my shop and it vents into the forest.

I don't have 2 delta TS's; one is a Delta shaper and it is on the same fence system.

I like the unifence and have a power feeder that attaches to the fence so I've never been interested in changing it. I looked at the incra TS fence the other day and it seems like there is a lot of walking and bending over required to change the fence position.

The slider is a Felder 741 combo machine. I picked it up late last summer and haven't really used it yet. It takes quite some time to setup.

The big blue thing is a 37" wide Halsty sander that I bought last summer.

AZ not only has green and trees but it also has snow. There is 2' on the ground now. Two years ago we had 17' of snow.


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## Grandpa (Jan 28, 2011)

mbs, I lived in AZ for 3 years. Tucson to be exact. We had some green in the summer and lots of green in the winter. We had people coming to ski Mt Lemon one winter. I asked from where? Flagstaff. Why would anyone do that? Snow was 18 ft. deep in Flagstaff and the lift chairs were dragging in the snow. That is snow.

So, David, what is the decision. Get a cyclone or not? You still need a filter system in the shop to clean the air you breathe. don't forget to budget something there. dust collectors pick up wood chips. Filters clean the air we breath. Good filters on the vac system are required or you will become part of the problem using them.


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## DavidNJ (Dec 10, 2012)

Which PSI model did you have. They have a 2hp with a 12in impeller than can't blow the fuzz off a dandelion. Its performance graph indicates marginal performance even with no ducting losses; it doesn't reach 600CFM at 4" of static pressure. However, their 2.5hp 14" model looks like it may be among the most cost effective solutions. An $1200 machine with shipping, Its graph shows over 900CFM at 8" of static pressure. They say it has a MERV 15 filter. I not sure where the ClearVue performance graph or table is located. They also have a 3.5hp/15" version that their chart shows over 900CFM at 11" and around 1300CFM at 8".

Grandpa…if you read my posts I was trying to understand the dimensions of the problem. My post in the other thread was clear: a MERV 15 or better filter with a cyclone to collect as much as possible and a 1-phase motor/blower capable of 750cfm-1000cfm at 7-8" of static pressure. That should include a a couple of Oneida models, a couple of Penn State models, and the ClearVue. It might include a couple of Grizzly models if they had the right filter, which they are calling me back on next week. On a price/performance basis the PSI models seem to be in the lead, the 2.5hp/14" impeller model with a 52"tall filter stack is $1100+shipping, the 3.5hp/15"impeller model with a 72" tall filter stack is $1300+shipping. Remote, bin full alert, muffler, and bin recirculator are options. The Oneida and ClearVue models are $300-$800 more. The Grizzly models are comparably priced but don't include nano-filters.

The ClearVue has the nicest looking cyclone…I can't attest to any performance advantage or if an advantage is significant to overall performance. I like its flow path form the blower to the filters, its clear cyclone, and the

I was trying to get my wife to consider by a house in a Phoenix suburb; she has one relative in the area. So far, no interest. I don't think they have any oval track racing in the Phoenix area; another hobby of mine.

In this thread I'm trying to learn real world experiences with the different cyclones dust collectors.


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## Dj1225 (Apr 27, 2012)

Hi I have been looking at the JDS 3hp cyclone, but have been unable to find much info..I like the engineering concept of this unit.. After taking the filter off my 1.5 delta collector, I realized that I certainly was not turning the filter cleaner often enough. The JDS has a motor that does this, which I like …...as long as it is reliable

It is just hard to believe with as much intermet presence as they have that there are no reviews.

Also they are the only company that talks about duct resistance, and a 15 .8 impeller is substantial. I live near their office in SC so if I pick up I can save a nice chunk of shipping cost. Only downside is not domestic..

I looked at clear view, but with cost to add remote and shipping this was going to be over 25% more and I still have to buy the drum. I am sure it is the best a lot of stuff to do.

Thanks


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## wapakfred (Jul 29, 2011)

David, no it's not too much power. The impeller is spinning at 3600 RPM, as per it's design. The first motor would not spin that fast (too much air through the ducts) and drew more power in an attempt to get to speed. That put it in an overload situation with just one gate open! The larger motor solved that problem. The problem with it is the basic design of the cyclone body. The dimensions/lack of air ramps/ inlet and that other stuff is why it doesn't separate the last drop of dust. BTW, I discussed the motor with Oneida before I did it….it was one thing they agreed would solve the overload problem I had. With units that are underpowered, letting more air in just adds to the problem, it puts more load on the impeller, drawing more power, etc.etc. Not so with mine, it's just hums along at the correct speed. But, good separation does require the proper air flow, and having the ducting choked down would reduce the separation of the cyclone…I've tested all combinations of that with no change….leading me back to the improper design.


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## ruel24 (Feb 14, 2012)

Dj1225, that JDS is the same as the Laguna.

http://www.lagunatools.com/accessories/dustcollectors/dustcollector-cyclone3m#

Maybe there are more reviews of that model? Here's one on Lumberjocks:

http://lumberjocks.com/reviews/1478


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## ruel24 (Feb 14, 2012)

And a Youtube video from Laguna:


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## DavidNJ (Dec 10, 2012)

DJ, this an American Woodworker test from 2006 that is on the Oneida site and include the JDS: http://www.oneida-air.com/PDF/AWW%20article%20jan%202006.pdf.

I'll let you judge if the JDS is the right machine. They said this about it: "Separation is good on the JDS. The 2 qt. of fine dust in the filter bag were far less than the gallons of dust in the some of the other cyclones' filter bags."

They said this about the PSI Tempest S 1425: "The 1425S we tested had excellent separation, with only a trace of dust remaining in the filter bins." On the Grizzly G0440/0441: "A mere spoonful of fine dust enters the filter bag from each barrel-load of shop dust." And this about the winning Oneida: "Separation in each model is excellent, with only a trace of dust ending up in the filter bin after the cyclone sucked up a barrel-load of shop dust."

Other than that they rate their filter a 1 micron, which would be a MERV 10 or 12. ClearVue, Oneida, and PSI rate their filters at MERV 15 or higher.

Filter maintenance is an interesting issue, the subject of a thread I'm about to start. Commercial baghouse systems (the industry name for filter only systems) have continuous compressed air cleaning. My guess is cleaning for a filter only system needs to be done after every use, and possibly several times per bin load. However, that is just conjecture on my part. As the filter clogs airflow goes down affecting dust collection from the machine but the clogged filter will trap smaller particles as remaining spaces are smaller. The trade-off is better fine particle capture by the filter vs. fewer fine particles captured by the dust collector to get to the filter. Cleaning can also wear out the filter or damage it if done too aggressively.

Pentz wrote: "Filter Cleaning - Worse, most of our filters wear out before they ever fully season. As our filters get dirty the air pressure rises enough to force the fine sharp particles to cut and tear their way through the filter pores leaving us with wide open filters. Cleaning does the same thing but faster. Most small shop woodworkers are a touch obsessive about how well we do things. Instead of a light shake or few taps we pull out 100+ PSI shop vacuum or our 120+ PSI air hose and really clean our filters. One heavy vacuuming or spray down can trash a new set of filters. These high pressure airflows really force the fine sharp particles to tear their way through the filter matrix."

The best trade-off on filter cleaning is not obvious.

Fred, I'm pretty sure your Dust Gorilla is working at the designed specifications, but I don't think it is a fundamental design flaw that is causing yours to suck your cyclone collection bin dry. Prior to the the ClearVue, the Oneida's, primarily the Dust Gorilla and Pro models, were the undisputed premium small shop/home shop dust collectors winning most comparison tests. Oneida probably wouldn't concede the crown to ClearVue; they would probably site a higher fine particle rating for their filters, the more rugged metal construction (vs. plastic and MDF), technology such as their Smart controls that adjust impeller speed depending on the load. ClearVue would probably site larger filter area, a better cyclone design, maybe a better impeller design, and a smoother path from the impeller to the filter. In practice, the difference between the systems is probably too small to detect except in a controlled, back-to-back experiment and insignificant from a practical standpoint.

Pentz had a forum post that also commented on a configuration that would such the cyclone bin dry. I'm looking for it. My hypothesis is that your ductwork is creating such high static pressure that the vacuum is emptying the dust bin. The proposed solution is to reduce the back pressure enough that it doesn't happen. The test would be simple.


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## wapakfred (Jul 29, 2011)

The only thing that would do that is a leak in the dust bin, something I've checked with every source of smoke stick I could fine, there is none. But thanks for your comments, as I said I've been over and over this with Oneida. They, btw, poo-poo Pentz's criteria. Good luck with whatever you choose to do, I wish you the best.


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## Grandpa (Jan 28, 2011)

They, btw, poo-poo Pentz's criteria. Good luck with whatever you choose to do, I wish you the best.

Fred, Anytime you have to put the competitors product down to make your product look better, then you are having a problem competing. That is what Oneida is doing with Pentz. Of course they wouldn't endorse his work because he didn't endorse theirs. He didn't put their work down though. If I went to Ford to look at pickups and they told me how sorry Chevys are I would walk. There is a problem with Fords in that case…..or the salesman.


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## exelectrician (Oct 3, 2011)

like Bill Pentz says it is all a dust pump with various grades of dust getting into you lungs, more expensive filter finer grade dust in your lungs.

Put the exhaust Outside


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## Manitario (Jul 4, 2010)

One of the main differences b/t the Oneida cyclones and Clearvue (and I think PSI) is the design of the inlet ramp; the design that Bill Pentz came up with was different than what was commercially available back in 1999 and unless Oneida, JDS etc has adopted his design (like Clearvue did) their's is different. In essence, the job of the cyclone is to keep almost all of the dust from reaching the filters, if having to clean the filters regularly is still part of the DC maintenance, then the cyclone is not efficient enough. I will go months between filter "cleanings" and still only have a a tablespoon or less of dust at the bottom of the filter cleanout.


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## DavidNJ (Dec 10, 2012)

ex, external exhausts are not viable for residential use other than an open garage because of the makeup air requirement. There are no viable makeup air solutions in this price range. Makeup air solutions are possible, especially in the winter, but the cost exceeds the cost of the dust collection systems we are discussing.

Rob, the question on the cyclone is: does it work well enough. Most probably do. The American Woodworker article the dust in the Oneida and PSI as a trace and the Grizzly as a spoonful. These are all rather tall cyclones with a reasonable design. The ClearVue probably is better…but is that difference significant?

If Bill Pentz's spec of a [email protected]" static pressure for one machine is the guide, the 5hp/15" CV1800 would be around 1250cfm , the PSI 3.5hp/15" would be 1050cfm, the 3hp/15" Grizzly would be around 975cfm and the 3hp/? Super Dust Gorilla at 800-900cfm depending on the chart you read. Net all are in the range…the ClearVue would be a little stronger but probably not in a significant manner (a Corvette is faster than a Malibu, both do 75mph on the highway with the Corvette a bit more likely to be doing zero while basking in flashing red and blue lights.)

Cost does vary a bit, but not enough to be a show stopper or make one a clear favorite The ClearVue would be $1950, the Oneida $1680, the Grizzly $1650($1350 plus another $300 for aftermarket nano filters), and the PSI $1300.

Fred, my hypothesis is that you have a well sealed ductwork…just not enough air entry creating too high a static pressure.


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## SASmith (Mar 22, 2010)

I think it works well. You should see the barrel after I use the drum sander.
It has less of a loss than the thein separator I used before and it separates much better.
I am planning on ordering a cartridge filter soon.


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## mbs (May 8, 2010)

I never see any dust discharge from my ClearView into the forest.


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## HorizontalMike (Jun 3, 2010)

Hey David. How about some pictures/images of your shop? It would be great to see what you have to deal with, you know?

Your race car was nice, but this is a WW site and we all want to see the shop.


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## DavidNJ (Dec 10, 2012)

mbs, you wouldn't see anything venting into the forest. Most that you would vent would be too small to see and rest is just a little powder that is most like disbursed by the force of the discharge. Your fine as long as none of your discharges are toxic.

Scott, your cyclone probably does work well. However, you may want to make the cartridge a priority. The amount of suction/airflow determines how much fine dust your system inhales but the filter is the major factor in determining how much it exhales…back into your shop.

Mike, my shop is a work in progress with a tiny 20+ yo Sears saw, a Hitachi 12" miter, an HF 10" sliding miter, and a Ryobi belt/disc sander. Hand power tools include a DeWalt circular saw, Bosch 470EB barrel jig saw, Bosch 1617 router with plunge, fixed, and when it arrives D-handle bases, an HF plunge router (not half bad), a couple of cordless drills, a couple of electric drills, one of the vibrating cutoff tools and then a bunch of metalworking stuff (note my picture), landscaping stuff, golf club building stuff, etc.. I'm rearranging to fit new arrivals. After I have the dust collector, saw, Incra fence (already ordered), etc. I'll add pictures.

The big issue is the saw…where I'm torn between the 3hp PCS Sawstop and a barely used Ridgid R4511 (which is really a Steel City 35920 with the miter slots cut in the center piece). One has safety on its side, the other has $2600. My wife says one saw related injury will make the $2600 look cheap.

I'm still undecided on the dust collection. If I had to make a selection this second I'd choose the PSI 1535 Tempest S with 3.5hp, 15" impeller, an 18"x72" MERV 15 filter stack with 700ft² of filter area for $1300 plus shipping. I'd run spiral duct tubing (the runs are pretty short) with hoods over and/or behind everything and blast gates to each tool. However, I'm still collecting information and haven't found anyone who actually has this setup. The closest is ND2ELK, who appears to be a very competent and knowledgeable woodworker, who has an older version of the 2hp/14 in impeller PSI system.


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## DavidNJ (Dec 10, 2012)

BTW…Happy New Year…


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## mbs (May 8, 2010)

I get a kick out of reading the detailed analysis about the dust collectors. When I researched dust collection systems I went through the same exercise in agonizing detail. But, in reality, when you're using hand power tools and older equipment it's a moot point about the efficiency and effectiveness of the duct collection system because the tools aren't designed to collect dust. The dust needs to be collected at the source to be very effective. I'm surprised manufacturers haven't caught on better.

I only have a few pcs of equipment that are great at collecting dust/chips. With the exception of SOME of the festool products, none of the portable electric tools are equipped to collect dust. As good as festools routers are they're still not great at collecting dust/chips. And the dust ports can't be used in all applications with the router. I have a newer Bosch miter saw that has a dust port. It's a joke. Only about half of the CHIPS go to the port. The other visible dust/chips hit the arm and scatter like mice. Who knows where the invisible dust is going but it has to be about as light as air so it's probably going everywhere.

I leave my DC on for 10 minutes after I'm done making chips to help clear the air. One guy with an air monitor recommends 20 minutes based on a study he did in his shop.


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## DavidNJ (Dec 10, 2012)

Happy New Year…

Hoods

That was another part of Pentz's recommendations: high airflow and hoods to capture the dust including a hood or ducted blade guard for the table saw.


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## mbs (May 8, 2010)

Got hoods on stationary equipment. You'll have to post your pics of the hoods you have for your portable tools.


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## RogerM (Oct 31, 2011)

I bought the Onedia Super Gorilla about 7 years ago. I believe that the only selections at the time was Onedia and Penn State. I chose Onedia as it was their primary product and that they have been business a long time. It still performs very well and I am quite satisfied with it.

I have two main 7"overhead metal trunk lines running out of it with 6" lines running off of the trunk lines. Most of the 6" lines are further reduced to 4" flex hoses and blast gates. Most hose runs are less than 6 feet and almost all blast gates are 4". I have at least 10 blast gates leading to the major pieces of equipment.

I am among the fortunate to have been able to design and build my shop from the ground up. This is the only major dust control unit I have owned so can not compare it. It is far better than all of the other combined small shop vacs that I have owned and plays a critical role in removing debris from my drum sander, 8"joiner and 15" planer.

If you would like further information send me a message and I would be happy to try and answer any questions that you may have.


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## DavidNJ (Dec 10, 2012)

Thanks, Roger. Which model Super Gorilla do you have? They currently have 2hp, 3hp, and 5hp models; Oneida doesn't spec the impeller size in their brochures.

All have the same size filter which Oneida specs as 110 ft². Oneida's charts show the 5hp has 1100cfm @ 10"static pressure, the 3hp has 800cfm. On the 2hp Oneida specs the operating range as 3" to 7" of static pressure. At 7" it is flowing about 780cfm on the chart.

Is only one blast gate open at a time in your shop?

mbs, your shop is impressive. I like the way you minimized flexible hose runs. Did you consider a hood for the jointer?

You are correct…hand tools are a bear. Bosch doesn't even have the adapter for their 470EB jig saw available. The miter saw ports on the back of the blade cover are border line useless. A cardboard box shell can help contain some of the visible saw dust, but the shopvac is pretty clueless on the fine stuff as it is ejected from a saw. It is better at picking it up off the floor. So far I've just been using ShopVac's drywall dust bags. Based on what I've learned in the past week or so, I have a HEPA filter and Oneida Dust Deputy arriving later this week. The hose was replaced last week with one with a smooth interior wall from Home Depot. Oneida has a bigger vacuum, the Dust Cobra, that is around $850. I'm also experimenting with a fine capture furnace filter behind a large fan.

My current solution? A 2 filter NIOSH P100 certified mask. Do you really want

I'm learning about the hoods and the source of the hoods now. Wood fabrication may be an option; it certainly would look nicer but the added weight would require a stronger support.

Within 2 months I expect to have a dust collector, table saw with router table, and hoods around everything. Pentz's diagrams for hoods are here: http://billpentz.com/woodworking/cyclone/ducting.cfm#DustHoods. Prefabricated sheet metal hoods may be available from some sources. PSI has some plastic hoods: http://www.pennstateind.com/store/specialty-machine-dust-hoods.html


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## Kelby (Oct 19, 2011)

I have a Laguna 2HP Cyclone. I run it with 6" spiral ductwork from PSI.

It is a huge improvement over the Jet bag system I had before. I previously used a Jet bagger with 4" PVC. There is a night and day difference with the new system. I keep a TV on in my shop, and when I used the Jet, I had to wipe the screen free of dust every couple hours. Now, I have probably wiped the screen once in the past year.

With that said, in a perfect world, I would have a 5HP ClearVue. I would like to have more suction than I have, even though what I have works very nicely. I went with the Laguna because it was cheaper and more convenient to buy and install. I don't like the fact that the big ClearVues are taller than my 8' ceiling, so I would have to do some construction to make it fit. One of these days I might make that upgrade, but for now, the Laguna does a very nice job.

A few nitpicks about it to be aware of if you consider it or the JDS that is similar: (1) Finding replacement bags for the trash can is a bit of a hassle; and (2) more dust/chips gets into the filter bag than is ideal due to the layout of the cyclone on this model.

On the plus side, the trash can is extremely convenient-there is a really nice clamping system, and that and the wheels make it super easy to empty the can. It is also an extremely quiet dust collector compared to other systems. It is far quieter than my Jet was, and it is also way quieter than ClearVue and other systems out there. Also, the included remote is very nice.

Good luck.


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## wapakfred (Jul 29, 2011)

I can tell you for sure the Oneida 2 HP impeller is 14.25", and (from memory, when they used to provide this info) I think the 3 &5 both use 15". But that is from memory and it is old info, they may have changed. I bought mine over 6 years ago when that info was available. They also used to sell the 2 HP model with a 2.5HP motor and a larger filter, which had some increase on air flow. I guess that one must not have done too well, doesn't seem to be available anymore.


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## DavidNJ (Dec 10, 2012)

Fred, is your Super Dust Gorilla is a 2hp unit?

Kelby, Laguna has an interesting variety of dust collectors. Most noticeable is the basic difference in cyclone geometry from ClearVue. Oneida, Penn State, and Grizzly. Those brands have a long cone, the Laguna models have a tall cylinder with a fairly short cone. Uniquely, they have a 3hp portable with automated cartridge cleaning. Which model do you have.

To all, I found two reviews on LumberJocks that you may find interesting. Both are by a Nova Scotian physicist and woodworker, David Goodyear (dlg). He reviewed his 2hp Grizzly G0440 Cyclone Dust Collector and Dylos particle meter. More importantly, he did independent testing of the dust level and fan curve.

In the first graph he ran a jig saw for about 20 minutes with the DC off. Then he turned on his air filter, then his DC. His description of the graph: "Started the jigsaw and cut for about 5-10 minutes. Since there were no air cleaners, vacuums or DCs turned on the air currents in the room were not influenced by any of those. Despite lack of driving air currents, the particle count rose significantly. The current plot shows the Dylos readings but to convert to cubic feet multiply by 100. THis means the particle count went from 20000 to 90000 just from the jigsaw creating dust being carried by the room air currents. About 15 minutes in to the experiment I turned on the air cleaner. Its a two stage home built air cleaner with a squirrel cage fan. It filters, 1 micron and the second filter has a MERV rating of 17. The particle count decreased to less than ambient readings in < 20 mins. This is good. My air cleaner is working. At 50 mins into the evaluation, I turned on the DC (G0440 2HP cyclone) and did some sanding with a spindle sander for about 20 minutes. The particle count continued to decrease. "










Note: dlg has a fairly comprehensive duct configuration: 









In his review of the G0440 Cyclone Dust Collector, a test restriction, and used a manometer an ammeter. He found performance greater than the Grizzly published fan curve, although a similar knee in the curve at high static pressures that the 2006 American Woodworker article showed. His graph shows slightly under [email protected] in static pressure. In conjunction with his particle measurements his results make it seem Bill Pentz's [email protected] in specification may have been a bit conservative.

Also interesting was his current measurements. He found they varied from 7.2 [email protected] 12.2in to 10.3 [email protected] 2.5in. That last measurement is about 3hp.










Has anyone done a similar test?


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## djg (Jun 24, 2012)

Since I am referenced in the thread I figured I should check in. First, not that any offence is taken, but I am actually from Newfoundland! But the rest is true about the physicsist, woodworker, and all the independent testing. I have all the equipment to measure fan curves, air quality, etc. I built a needle valve similar to Bill Pentz design and carried out testing similar to his specs. I was quite happy to see that grizzly had not cooked their data. Their measurements were done using a series of donut aperatures. My understanding is this will give some artificially high velocity measurements down the center of the duct and this is why a kind of needle valve works better. I reproduced the same fan curve on 3 seperate ocasions within the error bars on the graph.

I am pleased with the collector. For home use it is more than sufficient. My shop is 20×20 and it's cleaner than it's ever been according to my dylos meter which reads down to 0.5 microns. Even cleaner than my house! Collection at the source is key though.


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## Dj1225 (Apr 27, 2012)

Thanks for all the input on cyclones. I have decided to go with the 3HP JDS unit as I believe it will more than suit my needs and since I am close enough to drive to Columbia SC where they ship from, I will save additional freight fees. With all the savings, it will be almost $600 less than a clearview and I will not have to assemble. The size of the unit probably makes it a little less efficient, but as with everything in life there are trade offs.

I do have a question in regards to duct, that I hope everyone can help me with. Basically I run a Jet table saw off one port, one port works for my drill press, band saw ect. And the last port works as a modular station where I roll my router table, planer, and my 19" supermax sander.

None of the ports will be further than 15 feet from the dust collector, and the 15 " planer will literally be 5 feet away.
Given the proximity of my tools, do I need to run a 6" trunk, or can I use the 3, 4 inch connections on the supplied JDS machine. It is going to be quite a challenge to use 6" but if you guys feel it best, even on these short runs, I will man up and start the project this weekend.

Thanks


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## djg (Jun 24, 2012)

upgrade every port on your tools to 6" if the collector supports it. Use one machine at a time to maximize airflow. Using 3 and 4" duct will really choke your air flow and you will proabably be sorry you did it.


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## DavidNJ (Dec 10, 2012)

DJG, thianks for your input. Sorry for the geography error.

In operation, what is that static pressure at the cyclone in your system. Pentz targets numbers of 1000cfm @ 10", however your system is less than that and apparently functions fine.

DJ1225, In the American Woodworker test the JDS did a much poorer job of dust collection. While the Oneida Super Gorilla and Penn State Tempest S had a "trace" of dust, the Grizzly had a tablespoon, the JDS had 2 quarts.

Either the Penn State or the Grizzly would be less expensive than the JDS, even including shipping. The Penn State @$1295 plus shipping will be less than the JDS picked up at the factory, and comes with 700sqft of nano filter in the 3.5hp model (440sqft in 2.5hp model). The Grizzly is about $1450 plus shippling with a poly filter. DJG is using the 2hp model that is $1150 plus shipping. The Penn State 2.5hp Tempest S is $1095 plus shipping.

Equivalently equipped, the ClearVue is about 50% more, but comes with the satisfaction of the best researched design specifically for our application. The difference in cost, while significant on a percentage basis, is modest in absolute terms compared to the overall cost of the tools in the wood shops it is installed in.


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## Grandpa (Jan 28, 2011)

The ClearVue costs a bit more but are your lungs worth it? Piut a soda straw in each nostril and try to walk quickly around the house. You can't do it and that is what we will end up like if we breath dust for a few years and don't take care of our health. I went for the ClearVue on the presidents day special I think. It had a big package and was $1600 or a little over. I was advised by a man that had already bought 2 of the above mentioned collectors and had spent more money than he would have spent on my unit.


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## djg (Jun 24, 2012)

You want 800 to 1000 CFM at the source. I also measured the static pressures and air flow (CFMs) after my duct system was complete. I opened each gate independently and then measured static pressure and air flow several feet away from the cyclone inlet. All of my tools were above 900 except my router table, which I have now changed but haven't measured. Some of the tools were above 1100. I have been using my cyclone for about 6 months and I am getting ready to empty the bin for the first time. The amount of dust in the air filter clean out bag is several tablespoons. I am quite pleased with the performance overall and do not regret the purchase. I have 7" duct everywhere except at the tools it steps down to 6". I tried to minimize the use of 6" flex hose connection at the tools.

You really need to think about your duct design first. use Bill's spreadsheet for this. You can really get a sense of how much you are penalized in static pressure by adding turns, hoods, flex, changing duct diameter, etc. You just want to make sure that you duct size will support an air speed high enough to keep material from dropping out of the airstream on vertical runs. Most of these numbers are published on the web and are also in his spreadsheet.


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## wapakfred (Jul 29, 2011)

David, I have a question about the 2 HP Griz. Does it have the internal air ramp and neutral vane? My giuess is that with the superior particle separation you're getting, it does.


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## djg (Jun 24, 2012)

I should note, that all of my duct runs, even on my longest, most contorted run, is around 7" I think. Most are between 5-7 I believe. With regards to Grandpa's comment, I agree, somewhat. If you breath dust all the time, this will happen and other bad things will happen later in life. However, A dust collector should not be a replacement for a Dust mask. The levels of a dust collection strategy start with personal protection first and foremost. Everybody should be wearing a P/N 100 pleated dust mask, regardless of a dust collector running or not. Everybody should be vigilant about keeping the shop clean. Take dirty tools outside or clean up as soon as you are finished with the tools rather than waiting to kick the dust around the shop eveytime you walk to the other side. Using shop vacuums with hepa quality filters is best for this. Get a good dust collector, then add an air cleaner to scrub the dust that you do not get at the tool hoods. That's my strategy. it works, the dylos meter tells me so!


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## djg (Jun 24, 2012)

@Fred Hargis The Grizzly has an internal spiral air ramp and the port to the collector is rectangular and angled downward similar to the entry on the clearvue though probably not as efficient.


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## jusfine (May 22, 2010)

I have an Oneida Pro cyclone. The one on the right.










Bought it after using a simple bag system with a Veritas cyclone separator for many years. Had a mechanical engineer with DC installation experience design and install majority of my ductwork 2 years ago.

My shop is in the loft of our old barn, the cyclone is hung on the main floor, the ducting was run between joists below the workshop floor, coming through close to the tool location, then connected to the tool with flex. No ducting overhead in the shop.

I have an 7" main with 6 runs to 10 machines, branching off to use one run for two tools in some cases. All have a blast gate. Two runs are 5" (to jointer and planer), all others are 4" runs. Lots of suction!

We used spiral metal ducting, I bought the blast gates from Lee Valley.

If it is really cold (which is usually when I am in the shop), the radiant heater runs more often when I am using the tools constantly as the warm air is drawn out of the shop and the temperature drops a bit. Not enough to cause any issues. That is the only thing I have noticed that is a slight issue.


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## DavidNJ (Dec 10, 2012)

Randy, you have an advantage over most of us: the ability to exhaust outside.

David, you contribution is extremely valuable. Your readings are the only that are measuring fine dust and airflow in a real world environment. I think I am speaking for many here in thanking you for your work.

you have measured to insure you have 900cfm, even 900cfm is less than 3400fpm in a 7in duct. That is a bit slow for woodworking. Pentz specified 6", which can cause the air velocity to soar over 5000fpm, but ensures it will stay above 3500fpm (a low bound for woodworking) for airflows as low as 700cfm. The target for woodworking is 4500fpm; 6" duct achieves that at 880cfm, 7" duct needs 1200cfm. The penalty would bewood dust accumulation in the ductwork.


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## teejk (Jan 19, 2011)

I'll chime in here since I am still in the "study" phase. I've read (and believe) that residential ductwork might be a little flimsy for DC units. Think about commercial piping (23ga I think).


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## mbs (May 8, 2010)

teejk, not sure what you mean by flimsy residential ductwork. What type and size of ductwork are you referring to? What performance characteristic changes with residential ductwork?


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## djg (Jun 24, 2012)

@DavidNJ, I have 900 CFM on my planer and jointer. My table saw has 1000 and the downdraft, miter saw, drill press and spindle sander have over 1000 cfm. There is a distribution of air speeds across the diameter of the duct. The calculation for CFM from velocity pressure assumes the average velocity is 90% of the maximum. The flow in the middle of pipe is higher. Maybe this gives some advantage? DavidNJ, I agree with you calculations 100% but the proof is in the pudding so to say. I have one vertical run of 8' in a 7" duct. I have never had problems with matter dropping out of the air stream for my jointer (at the end of the duct run and material passes up the vertical run) or my planer, (close to the vertical run) which product the largest/heaviest matter.

@teejk I use 26 ga residential duct for mine and it is fine.


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## teejk (Jan 19, 2011)

MBS…Tin used in residential construction is lighter (28 or 29 ga I think). Commercial applications step it up to 23ga (I think). The thin stuff is pretty flimsy but for home HVAC is good enough since the blowers aren't that powerful. Not so sure the same can be said for a DC system but someone that has one can opine.


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## Grandpa (Jan 28, 2011)

I used spiral wrap pipe. I believe it was 26 ga but I am not sure of that. It is stiff and more difficult to work with than some of the elbows I am using. The elbos and wyes are stiff enout because of the opposing shapes they have. I used to teach a class in our local tech school. I remember the dust collector system sucking the pipe flat. It was put in by the boys from the heat and air class I think. It looked like a sheet of paper when that happened. Our collector in that building was an older generic commercial model. Must have had a decent motor and impellar though. 
Sheet metal is like wire. the smaller the number the large the wire.


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## teejk (Jan 19, 2011)

grandpa…any issues with dust collecting in the spiral stuff or is it simply a matter of which direction it points?


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## DavidNJ (Dec 10, 2012)

Penn State sells economy 26ga snaplock ducts for about $3.20/ft and 24ga spiral 'premium' duct for about $4.20. In framework of the overall system cost, a small amount. The spiral I'm familiar with has a much lower leak class than conventional snaplock, even if the snaplock is taped at the joints.

DLG, as your said, the results speak for themselves. However, have you inspected your ducts for residue? What was your actual fpm measurement? Did you profile the fpm across the pipe? What were the tolerances of your measurements? If the actual is 10% higher your ductwork numbers are in a safe range. If they are 10% lower you would be operating way below industry standards for woodworking.


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## teejk (Jan 19, 2011)

David…I had my HVAC guy price commercial grade (23ga) 8" round (that was the take-off on a model I was looking at)...$12 for a 5' section at the time (a few months ago). You're correct though in that in the whole vast scheme of things a $1 or 2 per foot is "spit".

And just to fill in the blanks, "snaplock" I think refers to a piece of tin where "some assembly required" (bandaids not included, swearing is allowed). Crimped on one end (male) to fit into the next piece (female). Flow direction would seem to dictate piping starts with the male end at the DC (might be wrong there but I had a 50/50 chance).


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## DavidNJ (Dec 10, 2012)

This is a PVC vs. spiral duct from Spiral Mfg.: http://www.spiralmfg.com/downloads/dust_collection.pdf

*Plastic pipe (or PVC pipe) *is unsuitable for dust collection for three reasons:

• First, plastic pipe fi ttings are not offered in the diversity required to meet design requirements.

• Second, plastic pipe elbows have a short radius, which encourages clogs and compromises system effi ciency.

• Third, and most important, plastic pipe is non-conductive and builds up a static charge as charged particles pass through it. This static charge can discharge at any time causing shock and surprise, which is dangerous around running machinery.

More serious is the risk of explosion and fire. Fine dust particles suspended in air have significant explosion potential-all that is needed is a spark, which the static charge on plastic pipe conveniently supplies. Grounding plastic pipe requires wrapping it in wire both inside and out-an expensive (and never certain) proposition that negates the minimal price savings in going to plastic in the first place.

*Spiral steel pipe* has none of these disadvantages. An incredible variety of fittings are available and custom fittings can be easily fabricated. The fittings are designed with long radius to minimize clogging, and special fittings such as cleanouts and quick disconnects are available. Most important, Spiral metal pipe is conductive, and simple and easy to ground, even when flexible rubber hose is used to connect the duct to the machine.


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## mbs (May 8, 2010)

David,

I want to give you some more to think about.

I know there is static charge associated with plastic and vac systems. My small shop vac shocks me every time I touch it and the outside of the hose has dust clinging to it with static electricity. I'm not poo pooing the concept of a possible fire. But in all the reading I've done, I can't find a single occurrence of a fire caused by static electricity in a small scale pvc system like I have. BTW, the article you're referencing is written by a company who has a vested interest in having you select metal ducting. I'm surprised people aren't boycotting SpiralMfg like they do Sawstop because Spiral is using scare tactics to encourage people to buy his products. At least in Sawstops case there are people who have lost their finger without the technology and nobody who's lost their finger because of the technology.

I've never done an actual survey but from the woodworking forums I follow I would estimate a 50/50 split between shops with pvc and metal ducting. If static fires were common wouldn't we hear about them just like losing finger or near misses? My wife works insurance claims for a large company that represents 25% of US homeowners. She's been working claims for more than 12 years and has never ran across PVC fire. I asked her if one had ever been mentioned in her group which represents the Southwest US and she hadn't ever heard of one being mentioned. Her cube mate was a leading experts on fires at the company and he laughed when she mentioned it saying it was an old wives tale. My mom retired from the same company with more than 30 years experience handling fire claims and she had never heard of an actual static fire. My step father retired with more than 35 years with both commercial and residential experience and he'd never heard of it. And, my wife said that the insurance claim would most likely be paid if there was a fire (not that I want any of the hassle associated with a fire).

Maybe the conditions for a fire to start in the pvc duct just aren't met. Does the air/fuel ratio reach a concentration level that will ignite? If they could be met, I think the spin chamber of the clearview would be a perfect place for a fire especially if someone forgot to empty the barrel and the dust/chips started backing up (I've done this - what a mess!).

Recall people being worried about their cell phone ringing while pumping gas at a gas station? Well, it's never happened but theoretically it could happen because there is a spark, fuel and oxygen. I recall watching a myth busters on it and they TRIED to start the fire and couldn't do it. Maybe we need a mythbusters show on this topic.

I would have to think if a DC fire in PVC were likely then we'd hear a lot about it in a forum like this or the other three that I frequent. The research I did certainly didn't exhaust every possible avenue but I definitely spent some time looking into it. I found many opinions on the subject but no facts. I would like other members to comment about their personal experience or well documented information from an UNBIASED source, but not here-say. Let's stick to the facts as much as possible because this topic is much like some other topics that get highly charged with opinions. I asked this same question on another forum and nobody replied with any facts or knowledge. I will add that the forum is much, much smaller that LJ's.

So, who has FIRST hand personal knowledge of a fire in a DC system? What were the conditions? E.g. running one portable sander? Running two planers at the same time? Running an angle grinder into the vac with a planer? Sucking solvent fumes and dust at the same time?

WRT fittings, over the years companies have increased their supply of fittings. There are wide sweeps available in pvc and it's fairly easy to make PVC fittings.

I personally don't care what people use, PVC or Metal, but, I hope to promote decisions based on facts.

I heard this a few years ago and I think the concept applies here regardless of anyone's religious beliefs "In God we trust - all others bring data". Let's dig up the facts and put this topic to rest!


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## teejk (Jan 19, 2011)

MBS…from what I've read, static caused spontaneous combustion is a real hazard in certain commercial applications but is only a theoretical possibility (so is getting hit by a meteor) in the vast majority of small wood shops. I do find a lot of comments from hobbyists about PVC static build-up (like causing their hair to stand-up) that as far as I can tell is only a nuisance. But I agree…trying to gain a "leg-up" by bashing the opposition (kind of like what we saw in the elections when you think about it) should automatically cause someone to apply an increased level of skepticism.

I'm still in design phase. I think the biggest problems with PVC is weight and cost when getting into the 6" category and above. And future "take-offs" would seem to be easier with tin.


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## mbs (May 8, 2010)

Teejk,

I too find a lot of comments about PVC. There were a lot of comments about the world ending when the Mayan calendar ended but we're still here. I'm hoping people will come forward with facts about the real hazard of PVC. I'm truly interested and not a proponent of PVC over metal even though it sounds like it from this thread. I just hate propagating misinformation (if it is misinformation)

Are you looking to have MORE weight or LESS weight? I looked at Spirals website and the 26 guage 6" pipe weighs 1.6 lbs/foot (24g is 2 lbs/ft) and KSC Direct 6" S&D pipe weighs 1.26 lbs/ft And, are you concerned about a couple of lbs in a 10' run?

Price is a factor that should be take into account. I took the first two prices I found online to get an idea of the prices since I haven't looked into metal in several years (this isn't a very good sample but it is an actual data point). The 26 gage cost $2.2/ft at royal metals and the S&D cost 1.95/ft. I would prefer to find it locally though. I know, for example, that 6" PVC is very expensive now where I live. It wasn't that way when I installed my first system.

Why do you think modifying a metal system is easier than PVC? One of the reasons I selected PVC was the ease of modification. I don't have any experience with metal but, if you wanted to make a wye in the middle of a run what would you have to do? With PVC, I just cut it with my sawzall and slip the wye fitting on each end. I may run a bead of silicone around it if I'm ambitious.


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## teejk (Jan 19, 2011)

mbs…I have no experience with S&D PVC (only sch 40/80 where I know it is HEAVY and pricey…maybe not that bad on the pipe but the fittings can kill the budget although in that regard, same can be said for tin). Will check it out.

"I just hate propagating misinformation (if it is misinformation)"

I agree on the first part. And glad you added the second part. There are so many opinions on this topic and little concensus…hard to tell what is fact vs. marketing hype.


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## mbs (May 8, 2010)

Schedule 40 and schedule 80 are heavier than S&D. 3.5 lbs/ft and 5.4 lbs/ft according to two websites. I would not use either of these. There is no advantage to having the extra weight or strength in a DC application. And, the fittings are more expensive.


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## Grandpa (Jan 28, 2011)

The Spiral wrap pipe is fairly smooth inside. The rib on the outside of mine is much larger than the inside. I chose this pipe because in the 6 inch diameter it was about as cheap as the plastic of the smae quality. I don't mind working with metal so I chose spiral wrap. I have read and I will say again I have read that there has never been a docummented case of a home dust collector explosion caused by static in plastic pipes. There is certainly static on them but then there is static on me when I touch my fireplace damper in the winter. I haven't exploded either. Document that. You cannot ground an insulator either. There is no such thing as grounding pvc. You can bond machines but there is a very good article on the internet (MIT written) about the false idea of grounding PVC.

Back in the old days when drip gas or condensate was blown out of gas lines into pits and burned people would steal it. I talked to some guys once that had a rig with a piece of plastic garden hose on the end of the pipe they screwed into the valve so they could put this in a barrel. They said the static caused by the flow in the plastic hose threw sparks all the time. With that said I am fairly calm about dust collectors. I never used this method for cacthing the drip gas but I know these guys never got injured and I believed them.

As far as buying long radius PVC elbows those are available. You might have to use the gray kind that is intended for electrical conduit. Conduit is more expensive than the white. We really should be using 45 degree elbows and wyes for dust collecting.

I had an advantage (I think) in my dust collector pipe. I live in farming country. I was able to get all the 4 inch diameter I wanted and some 5 inch aluminum irrigation pipe for free. Yes it cost nothing and it is rigid. I don't think I could suck that stuff flat with any dust collector system intended for a home shop. The outside diamter is the same as other 4 inch pipe.

When I went to the store to ask about the pipe I bought I asked about the 6 inch and the man at the counter said this is expensive. He checked it and I really don't remember the price. I asked him if he could get spiral wrap. Sure! He sold me 3 -10 sticks for about $126 including tax. That is what it cost in my area.

I will go on to say that the spiral wrap pipe is difficult to work with fitting I had available locally. I can see where their fittings would be good but who can afford those and electricity too?? I have said my pipe was 26 ga earlier. I am not sure if it is 26 or 23 but it is heavy enough. It was expensive enough too. I wish I could remember the cost on the PVC but it was high enough I back off from it and didn't hesitate to take the spiral wrap.

On the flow of dust and chips it might make a difference on the wrap if we were south of the equator…...LOL They have experimented with that in gun barrels in case you haven't heard. It made no difference.


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## mbs (May 8, 2010)

Thanks for the reply, Grandpa. I wouldn't be opposed to having metal pipe - especially if it was free.

I agree with using wye's where you can. In some cases I used two - 45's instead of a 90 but recently read from a published chart the the pressure drop is the same. It seems like it shouldn't be the same though.

Someone else, who appeared to be knowledgable about the differences between the two types of pipe, said the PVC is smoother than metal. It's hard to know who to believe without data.

I'll restate what I've said before. We're really picking fly crap out of pepper with some of what's been discussed in this thread. I don't think it matters if you use pvc or pipe as long as it's sized right. The DC brand probably doesn't matter as long as the motor and impeller are sized right. The most important part of dust collection, to me, is collecting it as the source before it's scattered about the atmosphere.


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## DavidNJ (Dec 10, 2012)

I posted the Spiral Mfg info as an example of the spiral duct argument, not as a definitive statement of my own views. Those views are still forming.

Spiral duct is wound like the roll of sanding paper on a drum sander. In contrast, 'snap lock' duct has a seam along the axis of the pipe. The spiral seam gives spiral duct its strength, not unlike beads rolled into sheet metal.

In practice, spiral duct is assembled in ways that create a very good seal. I would imagine PVC also creates a good seal. While it doesn't cause a fire, I believe one of its problems may be contributing to the spread of a fire. By the time its an issue, that may not be an issue for our small shops.

What do you do to get 45° branches in PVC?


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## DavidNJ (Dec 10, 2012)

mbs, the DC brand matters if there is a significant feature, performance, or price difference. The performance matters mainly if it insufficient. Similarly features are important only if they make a significant difference. How important price is depends on the size of your wallet.

I wrote this on a different thread, it gives some idea of the feature/price differences. Some features can be very significant. http://lumberjocks.com/replies/558748


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## mbs (May 8, 2010)

David, I use wye's to make branches. They also make 22.5 fittings if you aren't looking for a branch. I made my own wyes to go from 6 duct to my equipment using two 4" pipes. Each of them took less than 10 minutes to make. I made a 6" x 6" x 6" x 6" Y too. You can see most these fittings in my shop pics.


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## Grandpa (Jan 28, 2011)

I think PVC and metal should work equally well. I think dust collectors should work equally well but apparently they don't. The impellar design could be different and the cyclone could be different. If the RPM of the motor is the same then the impellar would be the next thing to look at I suppose. May the impellar housing could contribute to better collection. I don't think there is that much difference but I'll bet some folks think there is a major difference. If a system is marginal then I think we would see a difference but if the system is very goo then I think we could get by with a marginal housing or impellar. So how do we get a very good system without having a good housing or impellar?? If we have a good system we could get sloppy with our suction lines. I don't know. I do know I was in the Grizzly showroom in Springfield. I was looking at a 2 hp and a 3 hp model sitting there. Another customer walked by and said buy the big one so you don't have to come back and buy again like I did. HHHHHMMMMM


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## mbs (May 8, 2010)

I didn't select my words well. I should have said "the systems that have made David's down select list are good enough to collect dust. Metal pipe or pvc will work fine. The problem to be solved is how to collect dust at its source. Especially for David because few, if any, of his tools were designed to be used with a dust collector.

The fly crap & pepper point is this. A lot of time is being spent trying to eek out the most optimum system possible but it doesn't do any good if the dust containment mechanism at the source isn't superb. To me, it's analogous to to building a race car engine and mounting 6" lawn mower tires on the car.


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## DavidNJ (Dec 10, 2012)

Not optimum, but to understand the issues. Issues can be hidden. For example, none of the tests deal with fine dust, but Bill Pentz solely focuses on it.

My research strategy for most problems is to continue investigating until the amount of new, significant information becomes very small and infrequent. Sometimes this is accelerated by a pricing or availability issue. For example, I bought the Bosch 1617 router and some accessories to take advantage of Bosch's December sale. Overall, 5 separate purchases qualified for DeWalt's or Bosch's December promotion.

I tried making a hood today to use with the shopvac…a wasted effort. Once the DC is installed, I'll also install hoods over/around the different tools that don't have them. For the router table, the fence is one port, the second is a box around the router. For the miter saw, sander, etc. that have useless 2.25" ports, I'll try a hood and maybe fabricate my own box. I have a small sheet metal brake (although I often just clamp to a 2×2x.120 and hammer over with another. ) I also have a bead roller so it should be possible to give a sheet metal fabrication enough strength to withstand the vacuum.

For the short runs I have, spiral duct is probably my best solution. I'm still back and forth on the dust collectors. The selection, driven my performance and price, is between Grizzly and Penn State models (Grizzly has some very useful features, Penn State looks to be the better at capture) and 2hp and 3hp (Pentz's numbers and the vendors' fan curves would indicate 3hp, but David Goodyear's real world measurements indicate the 2hp is sufficient and the Grizzly handles fine dust adequately. Note, David Goodyear has well designed hoods and that his research is a sample size of one.

Grizzly sells (under the Shop Fox label) a room filter with an 0.3 micron filter. However, Sharp has one with similar or higher specs for about the same price with HEPA and charcoal filters. Reviews (from people with pet rooms, severe allergies, etc.) were very positive on the Sharp units. The Sharp unit would also have a modicum of VOC control.

Sidebar story: At one point I was having trouble getting my super late model stock car to handle. I had fixed a brake problem and my lap times were nowhere. I had lots of advise, many focusing on higher spring rates. In the end, I took control of the problem. I talked to the chassis manufacturer and reset the car to the baseline. That actually required changing the spindles. I bought quite a few springs and anti-roll bars and went to track testing days. We kept attacking the problem directly. Turn-in wasn't right so we kept softening the front and stiffening the rear. The front spindles were changed to get a different kingpin angle, the front upper control arms were changed to lower the front roll center. The rear trailing arm angle was adjusted to fix a power on oversteer situation. The rear springs became so stiff they needed helper springs to prevent them from unseating under braking. But slowly but steadily it got better and the lap times dropped and became consistent. I had a big smile when I came in from a session and the tach telltale said 7200rpm.


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## djg (Jun 24, 2012)

Just to chime in on the previous post. You will need to use a combination of strategies for some tools. The router fence dust collection will work best with a vacuum since a vacuum can easily overcome the static pressure associated with such a small opening. A vacuum will move air very quickly which increases the likely hood you can capture quickly moving particles that have high enough velocity to escape the spinning tool. The cabinet will probably work best with a collector as long as you have airflow around the bit and down through the table top. I am working on an over head mount that will collect above the spinning bit along with the vacuum through the fence port. A vacuum will not capture everything. Any fine dust escaping the bit will have to be captured with air volume. A collector works better for this.

The setup for my miter saw is similar. I use a tool actuated vacuum switch to turn on the vacuum while the miter saw is cutting. This is good for capturing the high velocity particles exiting the back of the saw. The smaller stuff will have to be captured using a massive volume of air surrounding the saw. I have a downdraft port behind the saw. The collector is always on while using the miter saw. My particle counter shows that I am getting everything. I will try to post a picture of the setup.

I will say that my 2HP machine is adequate for my needs. My research lead me to the purchase but I felt that I needed to verify for myself and others that the collector is doing what I expect it to. I will note in my design, I use 7" mains and 6" drops and only use one tool at a time. My reason for this is fairly simple. It was a trade off and a leap of faith. I knew that 6" mains would constrict airflow too much according to SP calculations and 8" would lead to excessively slow air velocities in the duct which would lead to plugging. I couldn't get 7" blast gates or flex hose but 7" duct was available. based on these variables, my initial plan was to run 7" duct (which I did to decrease the SP) run 6" mains to the machines and use a barometric damper at the end of my main run to offset the airflow restriction from the tools ports. This would add a little air to the air stream and increase the main duct velocity so to overcome plugging in the duct. I tried this but had a hell of a time adjusting the damper. Enough so that I abandoned it (for now). Despite this, the system still works and I have no plugging. My calculation of air velocity at the tip of the pitot gave velocities of >3750 FPM in the center of the duct. The velocity profile changes as a function of radial position in the duct but I am thinking that the turbulence at/near a transition is enough to force some of the lodged material back into the airstream since I have never had any blockages. This is my reasoning/speculation and hence my leap of faith.


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## mbs (May 8, 2010)

DJG - I agree with your logic. I never considered 7" because I didn't think it was available.

At my winter home I have two very poorly implemented situations. One is a square manifold at the inlet to the Thein separator where I have four 4" blast gates intersecting. It has to be very poor for air flow. I compromised the design to save space and I didn't want a "tree of y's across my wall. The second poorly designed and implemented feature is having a 4" duct run 35' long with two 90' in it. I should have used 6" for that. I did it as a test since it was cheap and easy to do. The long run collects dust from my bandsaw, infra router table and a stationary sander. I don't have any meters to check the efficiency but I've been happy with the visual performance. I would like to measure the airflow and the particle count but I don't want to invest the money in the instruments. I also have a wall mounted 650 cfm evaporative cooler that I run depending on the weather. I'd like to think that it moves airborne dust through the shop and out the open door. I't possible that it just keeps circulating the fines too. without measuring it I can't say for sure. I do know that my driveway has dust in it though but that's the dust we can see.

I have this yen/yang thing going on with dust collection. I spend a lot of time and money setting up the system yet half of the woodworking I do involves tools that create a lot of dust with poor dust collection capabilities (table saw with sled, routers, grinders, sanding contoured edges, miter saw). Sometimes I love the DC and sometimes I think I should just sell it all and be happy wearing a mask all the time. DJG - I would like to see your miter saw DC solution if you don't mind.

David, I'm sure you will end up with a killer system. It sounds like you have a lot of tenacity. Having sheet metal tools and experience is helpful. on a side note I was the VP-General Manager of a aerospace sheet metal company in my last job. I didn't come up through the ranks to learn the details about sheet metal manufacturing but I certainly have a lot of respect for those that can move metal where they want it. Early in my career I worked on jet engine impellers. We machine them out of Ti on 5 axis machines. Very interesting process.

I too tried making several hoods that didn't work worth a hoot. One was on my multi router. That thing was designed to create dust and through it everywhere. I haven't found a solution that gets close enough to the bit to collect the dust and not restrict access to the workpiece or motion of the table. Vacuums are poor at pulling particles that are more than a couple inches away. I'm starting to toy with the idea of using a fan to push the air to the dc port. Any ideas?


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## teejk (Jan 19, 2011)

mbs…seems to me that the fan is only going to create airborne dust (I get that simply by sweeping the floor).

Fine if you have the ceiling mounted air filter but I view that as second step in a shop, mostly because it seems like filter maintenance would be a bother what with step ladders and such so I would hope to capture most of it at source. I have mostly older tools so I don't expect perfection at all. My goal is to get most of it and minimize the airborne stuff that goes everywhere. I seem to spend way too much time with brooms and dustpans.

I've had a an older Leigh D4 dovetailer for years. A few years ago I was ordering new cutters from their site and stumbled across their DC accessory (shop vac). That makes a huge difference. Same for the Kreg pocket holer…must easier to use with a vac attached


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## DavidNJ (Dec 10, 2012)

dlg and mbs, do you have access to a CFD system? That should fairly definitively show what is need for hood design. I've seen it used for commercial HVAC, were in many ways it could be considered essential.

mbs, do you have a hood that can be used when the blade guard is removed? With enough airflow it should be enough to capture the fine dust which will follow the airflow. On the other hand, larger chips that are not suspended in the air require significant vacuum to move. They are an annoyance but not a health risk.

PSI has several fairly low cost ones in their catalog: http://www.pennstateind.com/store/specialty-machine-dust-hoods.html










dlg, what barometric damper did you try? The ones I've seen for residential HVAC are under 0.1" WG, compared to the 8"-10" range we are considering here.

Have you measured restriction with your ammeter? The current should drop from your baseline if there is a restriction, increase if there is a leak.

What drop in static pressure did you calculate from using 7" duct at 3750 fpm vs. 6" duct at 5100fpm, both numbers for 1000cfm. I'm getting around 1" WG per 25'. On the other hand, if an inlet restriction causes the airflow to drop, the 7" may drop to a flow velocity that is too slow for wood chips. One option I thought of is having a drop with blast gate to an automotive air filter (for noise attenuation). The blast gate could be used to regulate the flow, but some form of flow rate measurement (permanent ammeter?) would be necessary to calibrate the gate opening for each situation.

However, that may adversely impact collection at the tool being used by shifting airflow to the other port and reducing vacuum at the tool.


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## Manitario (Jul 4, 2010)

This is the best thread on LJ's right now…David you should rename it "Dust collectors of our Dreams" 
I agree with some of the previous posters that DC at the source is key. My biggest dust producer was my SCMS; I tried a bunch of complicated hood systems which were a PITA to use. When I upgraded to the CV I put the MS as close to the cyclone as possible and made a really simple hood for it; works great! I think it helps that it is the first collection drop in the system and I estimate the airflow to be about 1300CFM at the hood.









At some point I need to upgrade the DC for the BS; I have two 4" ports for the lower cabinet; they do an ok job, but I think if I used the BS more frequently I'd want better dust control. The difficulty with a hood type set-up for a bandsaw is that a) the hood invariably gets in the way and b) the airflow from the hood will suck up small pieces I'm trying to cut…

The TS is also a big dust producer which again, is not easy to control. I have a Sawstop which has a lower blade shroud which does an ok job of capturing the dust; I combined this with a Shark Guard with a 4" port; this does an excellent job at capturing the dust, however the problem is when I dado and have to remove the Shark Guard… I've looked at some of the large, overarm guards but they all seem rather clumsy and have rather small tubes ie. 2-3".

I went with snap-lock ducting. It was crazy expensive, but hey, it only hurt once. The nice thing about it is that I can easily change the configuration of my shop (as I've done a couple times). It also was easy to install and will be easy to take with me and use again if I move. Down side is that it is super expensive and that the "seal" between each pipe is not perfect and needs to be sealed with HVAC tape. There is the actual "Snap-Lock" brand of ducting which I think PSI and Woodcraft sells or the Kirk and Blum brand which is cheaper:
http://www.kbduct.com/


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## djg (Jun 24, 2012)

Here is how I collect from my miter saw. It is situated in my out feed table which is plumbed in with duct work for dust collection and vacuum. I collect out the back of the saw with a vacuum and whatever else escapes gets sucked in the downdraft behind the saw.













































The downdraft collects at 1007 CFM according to my measurements. This appears to be supported by the fact that I see no increase in small particulate in the air according to my Dylos meter after using the saw.


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## DavidNJ (Dec 10, 2012)

KBduct apparently also makes some standard hoods. As long as it is stiff enough to survive the vacuum and any environmental issues (material flying through it or object that may contact it from the outside) any of the ducting mechanisms should work. Leakage levels, pressure drop (either through friction or curve/branch dimensions and construction are the other issues.

JDS has a wire frame they put in their dust bin to hold plastic bags. Does ClearVue, Oneida, or Penn State have any solution for disposable cyclone bin bags?










The JDS also has an automatic filter clearer that operates on each shutdown. However, its short cyclone and small filter put it behind the leaders in core dust collection performance, both theoretically and as measured in the various magazine tests.

I've read about having too much suction on table saw blade guards (Shark Guard talking about their 4" model) and on router table boxes causing problems with the material being cut. Rockler adds an adjustable side vent on their router box to reduce the vacuum in the box; Lee recommended a 3" port on the blade guard. For open hoods, overhead or at or below table height, a screen may protect work items from being sucked in. It is a compromise not unlike the compromise made when seat belts first came into common use. In those days, outside rearview mirrors were less functional (poor positioning) and fewer (most cars had left side only, and at one point that was an option). We adapted… all cars now have two well positioned mirrors and some add an automated blind spot detection mechanism.

Any restriction-ducting, screens, etc.-can be overcome with more power and bigger impellers. However, different tools will have different restrictions. Should our dust collection systems have a VFD motor control to manage the flow for different tools by constraining the peak power in low static pressure circumstances?










(size is a little less than 6"x6"x5" for the 220v/3hp model)

Do you know the vacuum level/air flow in the chamber behind the saw? Are the vacuum port and the downdraft vent into the same plenum?

David


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## mbs (May 8, 2010)

Manitario - I can't recall what SCMS stands for.

I have the sawstop dust collection hood with works extremely well with very low suction requirements. I've heard it was designed by aero engineers. It's extremely efficient for everything but dado cuts or a cross cut sled cuts. It attaches to the riving knife like the shark guard.

My felder bandsaw only had one 4" dc port in the bottom bin. However there was barely enough space for a 4" hose to sneak under the table directly behind the blade. It's was a tight fit and will probably need to be removed if I have to tilt the table.

DJG - interesting portable downdraft table. I don't know why manufacturers don't put a big 4" port where they put their 2" port. It wouldn't be cool looking but it would be functional.

David, I rarely have an issue with too much suction at a pc of equipment. It's easy to regulate with blast gates.

here's a video of the multi router. forward to 2:18 in the video to see it cut. I've tried to come up with a hood for it but it hasn't worked well.


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## Manitario (Jul 4, 2010)

mbs: sliding compound mitre saw. 
The Shark Guard works very well, even with the giant 4" port that I have on it; I just wish that I had a proper solution for dado work without needing to invest in an overarm collector. 
David; there is a CV owner's forum on the CV site that has a number of users with different solutions for holding bags; from steel cages to having small amounts of suction to hold the bags into the bin.


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## DavidNJ (Dec 10, 2012)

The suction is how Grizzly implements, the wire bag holder is how JDS does. With a new tool, I'd like this to be worked out by the vendor.

If the features were equivalent, I'd probably pick the Penn State over the Grizzly; what I believe may be a slightly better cyclone and from the specs a better filter. However, the bag holder could be the deciding factor; the only empirical data is from dlg and it indicates the Grizzly is sufficient. There is a $700 difference between the CV and the 3hp Grizzly/PSI and a $900 difference compared to the 2hp versions. Enough to push me toward one of the others. The Oneida sits toward the CV side of the spectrum.

I didn't see comments on the CV forum about it. The parts from Grizzly would probably run about $100 to add it to another brand. It would require drilling a hole for the port and mounting screws into the cyclone. From the pictures they appear to mount the interface on near the top of the cone, with a tube facing up toward the impeller inlet. The other side mounts at the bottom of the collection bin.


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## djg (Jun 24, 2012)

@DavidNJ: I am not sure if this was directed towards me or not, "Do you know the vacuum level/air flow in the chamber behind the saw? Are the vacuum port and the downdraft vent into the same plenum?

but the answer to the question for my setup is that the elongated holes behind the saw are plumbed to the collector, the area (sq inches) is about equal to the area of a 7" pipe. I get 1007 CFM according to measurements directly behind the saw. having the blast wall behind the saw does help to contain some of the dust and direction of air suction. The yellow blast gate is plumbed to a vacuum that is tool switch actuated. Collecting out the back port of the saw with high velocity air is best. This is best acheived using a vacuum, not the collector. Unless you can design the hoods ie back port on the saw and the downdraft to have similar static pressures, the air flow through the main downdraft will completely choke any airflow though the 1.25 inch opening at the back of the saw through a vacumm hose.

David


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## Manitario (Jul 4, 2010)

DavidNJ:
http://www.clearvuecyclones.com/Bullentin/showthread.php?t=1177&highlight=dust
http://www.clearvuecyclones.com/Bullentin/showthread.php?t=1166&highlight=dust
http://www.clearvuecyclones.com/Bullentin/showthread.php?t=877&highlight=dust
I use a 30 gallon fiber bin from McMaster-Carr to collect the dust and just dump it into a bag when it is full. 
djg: nice MS setup!


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## DavidNJ (Dec 10, 2012)

This is a horrid website, worse video, but shows a miter saw dust collection system connected to a dust collector: http://www.rousseauco.com/downdrafter/index.htm. It would seem to work.










Vacuum specs (Festool, Oneida Dust Cobra) show peak suction at 96" and 70" respectively, peak air flow of 137cfm and 245cfm. However, Oneida also gives a more practical point for their $850 unit: [email protected]". This compares to the Grizzly 2hp whose spec sheet shows [email protected]" and max SP of 10.4". More practically, it has 1100cfm-800cfm in the 5"-to-8" range.

Is what is needed vacuum or airflow? The suction port on miter saws is in a very restrictive spot on the blade guard. There are online reports that show effectiveness varies greatly by brand; dlg's DeWalt being one of the better ones.

Unlike a circular saw whose blade is cutting up into the blade guard, the miter saw is cutting through the material rather than across it. In a sliding miter saw, bring the blade into the material is cutting as the blade is pulling the material off the work surface with the top unsupported. On the table saws and circular saws the blade is pushing the material into the work surface of the tool. Rather than throwing the material into the machine, the miter saw is throwing it up in the air.

Pentz shows two designs, both for a radial arm saw with a duct different than the miter saws. The lower blade guard is similar to a circular saw, moving totally out of the way. What was probably needed is a blade guard similar to the new models on table saws: independent left and right halves that ride on the top of the work surface. Combined with a wider top, at least on the side of the dust collection port, should provide enough suction, air flow, and entrapment.

No company seems to make that. The best that can be hoped for is a wider top with some sort of flexible scoop near the blade that directs material flying off it. Festool seems to have something in that direction.










On my saw there is 1/2" space between the housing and the blade disk on one side, 1/4" on the other, and 2.5" between the top of a 2×4 and the bottom of the blade guard. Net: the dust collection port is useless.

My initial attempt at a hood didn't work…not enough suction from a vacuum. I may resurrect it when I have my dust collector.

I have an idea for something that might work…but it may be hard to make a one-off (molding is probably required).

Those CV forum posts were funny. About 10 guys total, 3-4 years ago. A discussion of putting rocks in a plastic bag. Some adaptation of a leaf bag support. However, those require it to be slid out of a full collection bag. Easier to do with leaves outside than saw dust in a shop. I can't imagine how that can be done in a shop without sending fine dust in to the air in quantity. The problem is that it seems of the major vendors selling effective cyclone dust collection systems, only Grizzly has addressed the issue. Disappointing.


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## mbs (May 8, 2010)

One of the selling points of miter saws is portability and small working envelope. Festool probably has the best built-in DC in their KAPEX but the saw costs more than $1K. Most good DC setups for non-festool saws are about the same size as the miter saws.

Miter saws need to capture dust below the saw and directly behind the saw at roughly +/- 30 degrees of the blade to catch the roost. Having said that, I guess a thick piece of wood could be attached under the saw such that the blade doesn't penetrate the wood (like a radial arm saw) then the dust collection design only has to capture the roost.

Either a 4" hose off a DC would work or a vacuum would work with some type of mechanical funneling of the dust to the vac port.

BTW - the dust port on my RAS is useless. none of the dust makes it to the port. it's all roost! Here is a pic of my RAS. I have 2 -4" ports - one directly behind the blade and one off to the side. It does a nice job but it's a big hood.









Another design challenge is collecting dust for all the different compound angles that the saw can cut.


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## mbs (May 8, 2010)

Here's a pic of the hose going behind the bandsaw blade that I described earlier. The pic doesn't show much and I don't have access to the saw right now to take a better pic.


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## Manitario (Jul 4, 2010)

The Kapex probably has the best designed dust collection, but as mbs mentioned, the over $1000 price tag is a bit too steep for most…
I explored buying the Rousseau hood and I owned the similar PSI "Big Gulp" hood. The fundamental problem with the PSI hood and probably the Rousseau hood due to similar design, is that the dust port is too far back from where the dust is actually being produced. You can have a DC that moves a lot of air, but the distance between the port and the blade is far enough that the air velocity is poor at best, and not enough to capture the dust into the airstream. 
The issue with using the port on the back of the MS is that the design of the flap behind the blade really doesn't do much to direct the dust stream (with exception of the Kapex). As well, a 1-2" port cuts down the airflow dramatically. 
My solution as I posted above, was to bring the airflow from the DC as close to the stream of dust from the MS as possible; this captures the dust as it is thrown back off the blade. It's a simple design but I don't have any noticeable bump in the particle count in my shop after using the MS. 
DavidNJ; maybe I didn't send the correct links; some of the guys on the CV forum talked about running a hose b/t the cyclone and the bottom of the dust collection bin to equalize the pressure b/t the two so that you could use a bag in the bin without fear of it being sucked into the impeller. This is basically the same thing that Grizzly has done with their cyclones. I just have a small 30G bin, so it isn't a problem to dump it, but if I ever had the space for a 55G bin, I'd want to have a bag in it…


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## Manitario (Jul 4, 2010)

mbs; I like how the port is directly beneath the blade on your BS. I have 2×4" ports on the lower part of my BS; but neither are close to the blade.


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## DavidNJ (Dec 10, 2012)

Do your setups on the RAS and the miter saw work?

On the table saw the cuttings are thrown into the chamber beneath the saw and dust collection blade guard closely wraps the blade. For a sander, having a big hood works because the particles are very small…a gentle breeze carries them into the collector. From the saw the cuttings are larger, and the distances have to be shorter and the entrance paths restricted.

Note that a 6" pipe is 0.25 sq ft. 1000cfm is 4000fpm, which is 45mph. If the opening is 1sqft, the speed is only a bit over 10mph, a small breeze.

This review says the Rousseau hood works…but I have my doubts. It is two far away and has too big an opening. It does use its size as a big scoop and with the duct connection on the bottom leverages gravity. I have an idea for a design that would attach to the moving lower blade guard and act similar to table saw guard. It would have its own dust collection port and require the factory port be capped.


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## DavidNJ (Dec 10, 2012)

Back to dust collectors for a second. 

The Grizzly 3hp includes the muffler, a $49 option on the 2hp. Its replacement filter is listed as "new" with the high cost of $375. However, the 2hp's filter is listed as $475. For comparison the Penn State models' replacement filters are $240/pair for the 2hp and $320/pair for the 3hp. Clearvue charges $300/pair or $400/pair for their regular and nano filters respectively.


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## djg (Jun 24, 2012)

I don't worry about the filter cost a whole lot. It's a pretty easy mod to accomodate filters that are more financially appealing as long as you do some research to ensure airflow and SP requirements are met. There is a plan for a packed glass filter on Bill Pentz's site. Most mufflers work well if they are fairly long. The Grizzly has a short muffler. It's muffling capabilities are pretty small. The filter mounting brackets on the filter housing push the filter assembly fairly high with respect to the cyclone outlet. Even with the short muffler they offer as an option, you are hard pressed to attach the outlet flex ducts. You could modify the bracket mounting so to accomodate a long homebuilt muffler that would probably be much better than the Grizzly option. I opted for the Grizzly muffler only because I was eager to get back to my woodworking! I did not measure the sound intensity before the muffler was attached. After the Muffler was attached, I checked the dB using a sound meter app on my phone. It was upwards of 100 dB at 5-10 ft away so get good ear protection because most 2-3 HP machines are loud. If you modify the hoods on you planers, the spinning blades chopping through the high velocity air moving around the cutterheads gives a high pitched hum on top of the cyclone and planer motor noise. It will get noisy! It's good that the new shop addition can save your lung exposure to dust. Hopefully this means you will live longer. Don't forget that the longer you live, the longer you will need your hearing!


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## DavidNJ (Dec 10, 2012)

There is a review of the Penn State on this site: "There were three accessories I added to my dust collection system:
1. Cyclone muffler, which really makes a difference. It is quieter than a shop vac."


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## DavidNJ (Dec 10, 2012)

Talked with Penn State. They sell a $30 lexan liner for the bin that goes in side the plastic bag to support it. They say with the muffler it is 75dB,m which is line with the nd2elk's review. They also thought the maximum static pressure in my small shop would be 6" or so, and the 2.5hp would be more than enough.


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## Manitario (Jul 4, 2010)

DavidNJ; have you used the static pressure calculator on Pentz's site? I found it really helpful in trying to decide what cyclone I needed. 
FYI; that is an impressive DC setup you posted the pic of.


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## DavidNJ (Dec 10, 2012)

That was in a review here: http://lumberjocks.com/reviews/590. It is a 2.5hp Penn State with their muffler and their filter dust bin recirculator. Based on dlg's Grizzly noise comments and finding their cyclone dust bin bag solution it is again in first place. Their staff thought anything over the 2.5 hp would be too much.


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## mbs (May 8, 2010)

Manitario - you may be able to shove a hose in on your BS too.

David, the RAS dust collection works pretty well since I piped in the second collection point. It keeps the dust that escapes the primary port from making a U turn and coming back into my face. Also, the table top is almost like a solid Zero Clearance insert so nothing can get below the saw. I still get some dust deflection when it hits the fence but I can live with that.

The MS collection is a POS. I'm still deciding what to do with it. I didn't spend much time on it and it performs like a poorly designed system.

David - your airflow calculation are likely correct but the analogy to a breeze isn't very realistic in real life. A breeze (pushing air) will pick up particles that a vacuum system with the same airflow (pulling air) won't pick up. If I get the bug to improve my system AND I can't get closer to the blade then I may try to incorporate a fan to direct the air into a big gulp or something similar.

DJG - I was testing some new headphones and my neighbor lady was walking by with curiosity. I told her that my hearing was very important to me because as I age I what to hear every word my wife says when she's yelling at me. She thought that was very considerate of me


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## DavidNJ (Dec 10, 2012)

mbs, do you have a Dylos to measure airborne fine particles?


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## mbs (May 8, 2010)

No - I don't have any instrumentation to measure dust/airflow. I hate to buy it because it's the type of tool that you use once and stick it in a drawer.


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## DavidNJ (Dec 10, 2012)

That's true, but it is the only way to determine the efficacy of your DC on fine dust. Otherwise, we are just guessing. That is what makes dlg's analyses so informative.


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## mbs (May 8, 2010)

I agree. At some point I may solicit members to buy-in to some measurement equipment then we can mail it around to each other. Right now, I'm making furniture and don't want to spend more time on it.


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## johnlowell (Dec 22, 2012)

All this talk about sophisticated separators, motors and instruments. I am very interested in simple, better ducting. My small system is a 1 hp, 5 micron bag (yes, I need better) attached to a home built Thein, to a Y, then 10' lengths of spiral to the machines that may be reduced, or not. Supplemental shop vac (Fein) attached to dust deputy (small cyclone) that I have piped to blade guard on TS (2" flex hose) and of course use for all other clean up tasks (1.75" hose that came with unit).

Plastic blast gates are bad, dust collects in bottom, and then they don't close. Open, they have a small smile that impedes air flow. I heard rumor related to direction of air flow through gate, but no arrow on mine. Of course the spiral hoses are creating turbulence in the system.

1) Does someone make smooth bore interior flexible hose? If not, why not?
2) What is a good blast gate, 2" and 4"?
3) Have been installing equipment in a bunch on the presumption that shorter is better for the ducting, but this ignores any work flow, but that presumes I actually get work done.

Am a hobbyist, just want to keep the dust down and avoid permanent ducting.

tks, and I do note that this is a cyclone thread, sorry if this is slightly off topic.

cheers.


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## DavidNJ (Dec 10, 2012)

John, what is your objective? To pick up more visible sawdust? To capture fine dust that can lead to coughing and sinonasal cancer?

The overall result is a system that captures your objective and doesn't emit it past the filters. Which DC do you have?


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## DavidNJ (Dec 10, 2012)

mbs, I have a differential digital manometer, so measuring airflow requires a small piece of ductwork and a $90 pitot tube. I also have a sound meter and one in my cell phone. I need a TRMS clampon ammeter. The only thing that would be an extra purchase is the $300 for the Dylos particle meter.

If I had to pull the trigger today, I'm back to the 2.5hp/14 in impeller Penn State Tempest S. Still subject to change.

dlg, is the noise from the impeller outlet? The flow through the filters? The cyclone? The motor? The flow in the ducts?


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## DavidNJ (Dec 10, 2012)

Three posts in a row??? I have to get more organized!

When installing a cyclone, did you folks mount to an existing wall? Create a new frame/wall? Buy the manufacturer's stand? If mounting to a wall, would it make sense to drill into a concrete foundation or would it be better to to make a new wall section that mounts to the rafters on top and rests on the concrete floor?


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## johnlowell (Dec 22, 2012)

Well that is a good question. I guess my objective is health and safety, followed by reduced work i.e. picking up chips and fines. My current attempt is to simply improve on what I have and better gates and hoses sounds like a simple starting point. Trying to avoid manometers, vacuum gauges and anything involving heavy thought.

The actual DC is a Jet 650, I think their smallest system, may have to dbl ck the model number.

Perhaps other improvements can be at the operator level. I have not been cleaning the bag on any regular basis, but am thinking a blast or two of air would help after heavy use. The 5 micron bag is about a year old, was very glad to see the old 30 Micron bag go. That said, as I look into this, lot's to recommend a 0.5 micron filter, if I can even mount one on a small DC.

The Thien (sp?) works rather well, emptied the 32 gal can at 2/3 full yesterday, with very little getting through to the plastic bag on the DC. That said, the filter bag must be filling up with fines.

cheers


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## Manitario (Jul 4, 2010)

Hi John, 
I started with a similar DC, I had a 1.5hp General International DC with a 1 micron canister. I had several long lengths of flex hose attached to my machines; this did a better than nothing job at collecting dust, but I still was coughing after being out in the shop. I tried a few different mods, ie. bigger duct diameter, shorter lengths of flex hose, better blast gates but it really didn't give me the improvement that I wanted.

We can overthink dust collection and make it complicated, but the simple fact is that dust collection depends mostly on the amount of air moved, ie. CFM. To capture the fine dust from most dust producing machines you want to aim for a CFM of around 800. Every DC has a "CFM" rating eg. tech specs will state it can produce 1600 CFM etc. This is the starting point for the dust collector with no ducting, hoses etc on it. Everything you add onto the DC produces "static pressure" (think of it like friction) which reduces the amount of CFM the DC is capable of producing at the end of the pipe. Therefore, the greater the static pressure, eg. the longer the ducting/use of flex hoses/diameter of the ducting/use of a Thein separator the less the CFM. For small DC eg. 1.5hp the static pressure of even short runs of pipe quickly overwhelms the capability of the DC and you have limited airflow ie. less than what you need to capture fine dust. A DC can increase the CFM it is capable of at higher static pressures by two ways; larger impeller and higher HP. So…for an "average" 1 car garage shop, you can expect anywhere b/t 6-9" of static pressure, which for most machines will mean that you need at least a 2.5hp machine in order to have the airflow to capture the fine dust.

The reason why cyclones work better is that they do what your Thein separator is doing; which keeps the dust from clogging the filters which reduces the DC airflow.

I timed my purchase of a new DC with a move to a new house; based on a rough layout of my planned shop I calculated out how large of a DC I'd need…I bought a 5hp Clearvue, but a smaller 3hp unit would have worked as well for my shop (2×20' runs of 6" steel duct).


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## DavidNJ (Dec 10, 2012)

John, this all depends on your budget. Let's assume you don't have one.

First, you need a canister. The Jet 650 had a model with one, but it seems to have been a bit on the mediocre side. Wynn has one but needs a little adaption work: http://wynnenv.com/notes.htm. That will keep the DC for throwing the dust it collects back in the air. You will need to clean the filter regularly. Wynn can give you an idea of how often.

Your Jet 650 is a tiny little thing on wheels. Forget about ducts and blast gates. You aren't going to use any. You are going to wheel the unit right next to the machine you are going to use and connect it with the shortest duct that will work. If some of that can be rigid duct that is great; rigid duct has much lower pressure drop. But think short and direct. You want static pressure drops under 4".

Even then the system will be marginal, but you will have as much airflow as you can get to trap the fine dust and a filter that keeps it in the system. Cleaning the filter is essential because a dirty filter will reduce your airflow.

The advantage of the cyclone over the Thein separator is that the cyclone has a lower pressure drop (but still significant) and is more effective and efficient at removing fine particles from the airflow.

Commercial systems just use the filter. The filter is outside and a makeup air system (which costs more than an expensive DC and table saw combined) replenishes the air in the shop. The filter is cleaned by an automatic pulsed compressed air system.

The cyclones are a more expensive solution to separate the dust before the filter. However, since we don't have makeup air or automated filter cleaning mechanisms it is the better home shop solution. Grizzly rates the no load airflow (about 2.5" SP) about 20% lower for a cyclone. For example, their 2hp model is at 1700cfm for a canister, 1350 for a cyclone.You really don't have the power to have sufficient airflow and a cyclone/Thein separator/etc.

From a health standpoint you are less concerned with chips than with fine dust. You can always vacuum the chips. You will have already breathed in the dust.


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## johnlowell (Dec 22, 2012)

Wow, tks for all the information. I can take out the Y's and blast gates, the only impact will be the ease of shifting from one machine to another, but perhaps the price to pay for a small DC. It is unfortunate that better performing accessories do not exist.

Will look into canisters, but from what I am reading,sounds like trying to make the proverbial silk purse from a sow's ear. Need bigger unit.

tks again.


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## DavidNJ (Dec 10, 2012)

Well…yes…you could use a bigger unit. Even then, the least expensive solution with a cyclone would probably be over $1200 with delivery charges. On top of that you would need ducting, blast gates, etc.

Here you need one hose, quick release clamps, and an upgrade to a cartridge…which with adapters would be under $200 (the cartridge parts). You could get a 1.5hp or 2hp new non-cyclone unit with cartridge for about $500 delivered. You would still need to clean the filter.

This thread talked a lot about fine dust, but only one person on the thread bought a device to measure it. Most people are unaware of the issue or ignore it. The vendors for hobbyist equipment either don't make a big point of it or provide minimal real information.

Even Bill Pentz doesn't provide actual measurements for real world workshops. If we had an accurate measurement of fine dust in 1000 shops with different dust collectors, ducting, machines, and hoods we would be able to make informed decisions. Instead we reference theory and 5 year old webpages with little or no empirical data.

The key to remember is it is an end-to-end system: from capture at the source of creation to retention in the system. A bag filter with really good hoods at the machines could perform better than a cyclone with HEPA filters and poor capture at the machine. Keeping the airflow volume up is all about the capture at the machines. The cyclone, while it looks impressive with is bin of chips at then bottom, is really just about keeping the filter clean.

Here is one person who tested two shops for a different view: http://woodgears.ca/dust/dylos.html.

Note, irrespective of what that article says, wood dust has been correlated with sinonasal cancer, although there isn't enough data to determine what level of exposure is necessary to cause a statistically significant risk.


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## mbs (May 8, 2010)

Don't forget craigslist. My jet 2 hp unit was $175. I put a wynn filter on it which added to the cost but it's worth it.

There are at least five 2 hp DC on craigslist right now under $200. One is $100.

I recently sold a 1 hp system for $70. It was a good deal for someone who wanted to collect chips from his table saw.


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## Manitario (Jul 4, 2010)

"but only one person on the thread bought a device to measure it"

I have a Dylos particle counter as well; I wish I would have had it prior to upgrading my DC so I had #'s to compare. There used to be a # of threads on SawMillCreek.org with guys who had bought Dylos meters, that was what gave me the idea to buy one in the first place. 
I don't get particle counts as high as djg in my shop without my DC running; typically I'll average b/t 6000-9000 with the DC off. With the DC on the average is b/t 100-300 (my house air is 400-500). My father-in-law has my old 1.5HP DC in his small shop; connected up to his machines with short runs of 4" PVC pipe and flex hose; he lives 8h away, but next time I visit I'll try and bring my Dylos to his shop, it would be a perfect comparison; especially as this seems like the typical setup for the average LJ.


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## b2rtch (Jan 20, 2010)

" Don't forget craigslist." 
I live in SLC Utah and there is never anything on the CL here.
We have KSL Classified , a much better resource.


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## mbs (May 8, 2010)

I worked and commuted to Utah and kept checking Craigslist for deals. It was totally lame. I talked to someone and they turned me on to KSL. It is better than Craigslist in UT but Craigslist is very useful in Phoenix. I sold something today on craigslist and made an offer on something else too.

You can still search Craigslist for things in other cities and find deals. There's ebay too but the prices are generally much higher.


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## teejk (Jan 19, 2011)

Rob…I don't need a meter since I have glass installed in my shop door and the airborne stuff is easy enough to see. And David, no need to bring up sinonasal cancer (unproven but relatively rare even if it's true). If you really want to live forever, sell all your tools, your cars, your house and certainly get rid of your cell phone. Buy a bubble (with HEPA filtration).


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## Manitario (Jul 4, 2010)

teejk; fair enough, the low tech way is definitely cheaper than the Dylos! I'm not particularly concerned about sinonasal cancer, your're right in that it is pretty rare; I am concerned about asthma and COPD though, which unfortunately are pretty common.


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## DavidNJ (Dec 10, 2012)

Unless you're up this member of the team of Mr. Fantastic, the Human Torch, the Invisible Woman, and the Thing, I doubt if you're seeing items in the 1 micron range, about 4/100,000 of inch.

I'm still waiting through the Sawmill River threads in some of the name-calling that goes on there. This thread has been a lot more civil although that thread and people whose income depended on it.

For some their greatest weakness is that the dust collector. For nearly all of us, the hoods we used to capture are equally great if not greater problem. One of the reasons we don't focus on it may be that no vendor has found a way to make money selling the hoods.

What we see available is an occasional plastic molding or generic metal fabrication. What we need are fitted items that don't impede access to the tool but capture all the dust within inches of its creation. The Shark Guard tablesaw blade guards are one example; but that is only a small company making him for very limited audience. I doubt one 10th of 1% of tablesaw owners ever heard of the Shark Guard.

The problem is the wide number of different devices and the difficulty fitting to them. And that only a small percentage of the tool owners are even aware of dust collection issues and only a small percentage of them have aggressively addressed it. For example, my guess is over 3/4 of the people on LumberJocks has a dust collection system with enough airflow to make the hood selection the biggest issue; why worry about collecting 5 micron if you will send them back into the shop past the filter?

This is a graph posted on the other forum 4 years ago by a new Dylos user. You can see that this dust collector, described as a 2hp Taiwanese cyclone which probably means a Grizzly, is cleaning the air. It is also not capturing the dust coming off his saw. His dust collector, which I think is similar to dlg's, seems fine. His hoods at his tablesaw seem inadequate.










This paper is one of the few I found that don't require a subscription to read: http://www.jniosh.go.jp/en/indu_hel/pdf/IH_49_4_492.pdf

It contains some electron microphotography that some may fine interesting. teejk probably won't find it interesting, since he can see the particles with out any aids by using his glass door.


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## Upraiser (Dec 24, 2012)

I have the Oneida Super Dust Gorilla and I am very pleased with it. I replaced a 2hp Grissly with impoved dust bags. I had it in another shop and it was adequate, but did put a lot of fine dust in the air so I added a room filter unit. I thought it was adequate, but last fall I developed some breathing problems so I took a good look at the whole system. I had a 5" line with only two bends that connected my table saw I was having some dust buld up in the cabinet. The system was not working. I had read several reviews on DC systems and te Oneida system always came out on top. If I was going to continue wood working I needed to solve the dust problem.

My old system was ceiling mounted to eliminate as many bends as possible, I already had all the 5"ducts in place, but Oneida has an 8" inlet and they recommended an 8" main line but agreed that my 5" was worth trying. I seems to be working fine. The table saw is at the end of the line, 32' of pipe from the DC, I leave gate open all the time, I have a 4" gated to a jointer, a 4" gated to a miter saw and another gated 4" to several toolls on rollers, a large shaper, drum sander, planer, belt sander and large resaw band saw. I use the drum sander a lot.

I have checked the HEPA filter on a regular schedule, blow it out each time and have yet to find the clean out container full. I no longer have a breathing problem, the table saw (a 10" Unisaw) remains clean and the only time I run the room airfilter system is when I do some routing at the workbench.

I will upgrade to an 8" line as I am adding a larger system to the miter saw and adding some sanding equipment.


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## mbs (May 8, 2010)

I'm happy to see the focus of this thread starting to turn more towards capturing dust at it's source.

I hand't heard of a shark guard until I read this thread. It's similar to the sawstop guard.

David - you're absolutely right. We all think our system is adequate but very few of us have the tools to measure adequacy. This is a case where you can't see the real enemy.

I'm hoping this thread, as well as others, will prompt people to contact the manufacturers and let them know dust collection at the source is something we care about.


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## DavidNJ (Dec 10, 2012)

Curt, you didn't say what size Super Dust Gorilla you had. If it is 1-phase, it is either 2hp or 3hp.

Either way, 5" is too small and 8" is too big. Your two requirements are a target airflow speed of 4000fpm (min 3500fpm) in the duct and a total airflow over 800cfm and preferably over 1000cfm at each machine. That should show a 6" duct is correct or a little too small (2hp cyclone) or a 7" is correct or a little too big (3hp). A 5" duct is at 5900fpm

```
800cfm and 7300fpm
```
 1000cfm. A too small pipe has significantly higher pressure losses reducing airflow. A too big pipe lets wood particles collect in the duct.

mbs, the SawStop guard has a tiny 2.5in port, the Shark Guard comes with larger 3" or 4" ports. Unless you use an overhead mount neither deals with cutting with the guard removed (e.g. with a crosscut sled or a dado blade).

And that leaves all the other tools. A woodworker doesn't live by a table saw alone. That router/router table creates lots of dust also.


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## HorizontalMike (Jun 3, 2010)

IMO, often overlooked our WW-shops is overall adequate ventilation. I open my 8'x16' garage door every time I have the chance. I am blessed to live in the deep south and my shop is a stand alone metal building with a minimal R5 insulation. Rarely have to heat and never cool. Understanding that, I understand that for folks with shops in their basement enhanced ventilation is, or at least should be, of a much greater concern.

My point is that it is important to have that turnover of air within the shop. Air-toAir Heat Exchangers probably should be included in this DC discussion as well. This could/would take some of the load off of our other DC and air filtering equipment.


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## mbs (May 8, 2010)

Without measuring actual dust it's hard to know the efficiency of the sawstop system. It has a blade shroud under the table with a 4" DC port and the small port over the blade. I get almost no visible dust during rip cuts but, as I mentioned before, it doesn't work with sleds or dado's.

I live in AZ. 90% of the time i'm in my shop I have two doors open. One is a 16' door and the other is a regular entry door. On warm days I run a 650 cfm cooler. At my other shop I have 10' x 16' doors at each end of the shop and get good air flow. I have a 16' x 16' covered patio that I like to use for sanding and routing.

I just can't get my head around working in a basement. I'm sure if it was my only option I would learn to like it.


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## DavidNJ (Dec 10, 2012)

I'm in a basement that has three tiny windows and is not included in the house's HVAC system. I've been considering a ERV for the house, but not for the basement. It is tricky to put in for either since the basement doesn't have any walls to mount the vents. It is also possible a high dust environment may clog the unit.










The cost would be at least $800 for the unit. But it would need a separate blower and installation. Net would probably way for the entire 2.5hp cyclone with ducting.

My garage is already consumed with cars that aren't weather tolerant. In my climate a shed would have to be heated and probably cooled to be useful in much of the year.


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## HorizontalMike (Jun 3, 2010)

"...I'm in a basement that has three tiny windows and is not included in the house's HVAC system. I've been considering a ERV for the house, but not for the basement. It is tricky to put in for either since the basement doesn't have any walls to mount the vents. It is also possible a high dust environment may clog the unit…"

Sounds to me that one of those basement windows could/should be dedicated to an Air-toAir Heat Exchanger. You could even build an enclosure outside to house the unit, thus making it easier to service/maintain. I truly believe that this is much more than just a 'convenience' piece of equipment. After all, why is it that basements have a reputation for poor air circulation, mold, mildew, etc. And think of all that micro-dust you plan on introducing as well.

I would put the basement as priority over the rest of the house for ERV, if it were up to me.


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## mbs (May 8, 2010)

Where do you live, David?


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## DavidNJ (Dec 10, 2012)

New Jersey…there for the moniker DavidNJ.


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## tme4tls (Mar 21, 2011)

Fred Hargis - I also have an Oneida with the same problems, constant clogging of the filter. Oneida said I had a leak between the cone and barrel then I spoke to a man who said I needed an additional filter so I would have to clean them out half as often. So I dumped the filter and installed a bag house which is much easier to clean, maintains a good airflow and does not require constant cleaning when the barrel is emptied.

So what exactly did you do to the cone to make it more efficient?


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## Upraiser (Dec 24, 2012)

David I have the single phase 3hp unit. I attached it to the wall near the ceiling so the duct is striaght off the intake. It has an 8" inlet and Oneida suggested I replace the 5" with an 8" duct, after laying out the $ for the system, I had a cheep and put a reducer on the unit and used the existing duct system. It works fine, but I would like to boost the intake at the 12" Dewalt miter saw. I have a 4" off the 5" with a "y" joint. I pick up the fine dust, but it leaves a lot of sawdust behind. I have tried a few things that did not help. I need to put in a larger duct off the main line then neck it down in two steps to a 4" and perhaps a 3 to a 2 to a flex hose with a direct connection to the saw.

The table saw is 32' from the DC and the only dust I get is a litle off the top from the saw blade and once again it is only the heavier saw dust.

The system works fine with the 5" open along with 3 of the 4" open, usually shut down one other 4" gate when I run the planer or drum sander.

Thanks for the comments.

Curt


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## DavidNJ (Dec 10, 2012)

My only guess why Oneida recommend 8" duct is they thought your system had very low static pressure from the short runs. In a 6"-7" static pressure range the 1100-1200cfm would have indicated 7" ducting. However, with 32' of ducting, I'm not sure how they arrived at that.

As far as " the only dust I get is a litle off the top from the saw blade and once again it is only the heavier saw dust": you know that how? On the table saw the blade pushes the heavy stuff under the table. There is lots of dust above the table your are using your respiratory system to filter.


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## DavidNJ (Dec 10, 2012)

I forgot to post the fan curve:


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## mbs (May 8, 2010)

I don't have any experience with measuring air flow. is this what I need and is it in the right range?


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## teejk (Jan 19, 2011)

is anybody building a DC system here or are they simply talking about it (or selling something)?

I asked somebody for the time once and I got detailed instructions on how to tear my watch apart and put it back together. 133 posts tells me I have a deja vu moment.


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## mbs (May 8, 2010)

I'm not building one. I may modify it though. Fair question though.


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## Manitario (Jul 4, 2010)

teejk; I've built mine already and I'm happy with it. There is a lot of mis-information about DC though, I look at this thread as a discussion of some of the important issues surrounding building an effective DC system eg. duct size/dust capture at the source/CFM requirements/testing, as well as a quantitative comparison of some of the DC systems out there. 
There are a lot of different DC systems available and a lot of mis-information about DC; rather than tell someone "buy this" it's more important that they are able to examine what sort of DC they need by considering themselves all the factors involved in proper DC.


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## DavidNJ (Dec 10, 2012)

I putting one in within the next 4 weeks or so. The purpose of this thread was to get input from people who actually owned cyclone dust collectors.

Based on the input I will probably end up with the 2.5hp Penn State Tempest S…but that is still subject to change. Some of the technical parts have been discussing nuances of different individual installations. Every installation has nuances. Even with the best home shop cyclone dust collectors, capturing dust as it is generated is always an issue. Tool designs rarely have fine dust collection; for example, SawStop illustrates their dust collection with a video of visible dust in a bin rather than an airborne particle count of respirable (<10micron><1-micron>:http://www.aiha.org/education/meetings-conferences/aihce/archivedabstracts/2011abstracts/Documents/2011Abstracts_WoodDust.pdf

mbs, to measure velocity you need a calibrated pitot tube and a differential pressure transducer. The pitot tube produces two pressures, one static, one dynamic, and determines the velocity based on their difference and the density of fluid. That is a differential manometer, but a digital one would be a lot easier: http://www.amazon.com/gp/product/B002R1RWWE/


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## mbs (May 8, 2010)

David, will the manual manometer shown work?

I hadn't seen the sawstop video. I've been touting their dc capability but I had't see proportion of dust captured below and above the blade. So, when you don't/can't use the blade guard a lot of dust goes airborne and it's all directed at the operator! I use the blade guard whenever possible.

thanks,


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## DavidNJ (Dec 10, 2012)

I think so but I don't have any first hand experience. The risk is blowing it out since the differential amount (about 1.5") is much less than the level on either side.

I'm thinking there has to be a fairly tight above tool duct for any tool. Maybe a hood on the table saw, but it probably needs to be shaped for other tools to keep the inlet area reasonable.


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## mbs (May 8, 2010)

At some point I may solicit fellow LJer's to pitch in on some measurement equipment that we can send to each other. It's the kind of thing that you only need for a week or so and after that it just collects dust. Or I may buy it and sell it when I'm done.


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## DavidNJ (Dec 10, 2012)

The cost of the equipment-Dylos particle tester, pitot tube, differential manometer, clamp on ammeter-are low enough, about $600 combined, that sharing the cost probably doesn't make sense. The cost savings from sharing won't equal the hassle. Woodworking is expensive enough that $600 for measuring dust collection efficacy in a shop with $4000-15,000 of equipment isn't that big a cost.


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## DavidNJ (Dec 10, 2012)

From looking up some stuff on MDF I came across an MSDS with the occupational specs for wood dust and definitions.

First, definitions:

"Inhalable aerosol fraction" is the fraction of total airborne particles that enters the body through the nose and/or mouth during breathing. This fraction corresponding to particles with aerodynamic diameter (dae) ≤100 μm) is relevant to health effects anywhere in the respiratory tract such as rhinitis, nasal and lung cancer and systemic effects.

"Thoracic aerosol fraction" is a sub fraction of the inhalable fraction [dae < 30 μm] composed of particles that can penetrate into the tracheo-alveolar region of the lung and is important for asthma, bronchitis, and lung cancer.

"Respirable aerosol fraction" (or alveolar fraction) is the sub fraction of the inhaled particles [dae <10 μm] that penetrates into the alveolar region of the lung (i.e., includes the respiratory bronchioles, the alveolar ducts and sacs) and is pertinent to the development of such chronic diseases as pneumoconiosis and emphysema.

Next, the limits:


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## mbs (May 8, 2010)

David, what are types "Twa" and "Stel".

On a side note. I went to a cabinet shop auction. They had 3 or 4 dust collections systems. Each system had a 250hp to 300hp motor and the main trunk line was approx. 2.5' in diameter. I didn't follow the bidding closely but I think each system sold for around $1000.


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## DavidNJ (Dec 10, 2012)

TWA is time weighted average. STEL is short-term exposure limit. 8-hour TWA permissible exposure limit (PEL) is defined as:

"TWA is the employee's average airborne exposure in any 8-hour work shift of a 40-hour work week which shall not be exceeded."

It is clear the ACGIH (used in Europe) are much more restrictive than the US limits. We may not be that far away from US OSHA with table saw operation with the 2+hp cyclones. However, we are probably way off on other shop operations.

And some more form OSHA:

*EXPOSURE LIMITS *


OSHA PEL

The Occupational Safety and Health Administration (OSHA) has established a permissible exposure limit (PEL) of 15 milligrams per cubic meter (mg/m(3)) of air for the total dust and 5 mg/m(3) for the respirable fraction of wood dust, all soft and hardwoods, except western red cedar (as a nuisance dust) [29 CFR 1910. 1000, Table Z-3].


NIOSH REL

The National Institute for Occupational Safety and Health (NIOSH) has established a recommended exposure limit (REL) for wood dust, all soft and hardwoods, except western red cedar of 1 mg/m(3) as a TWA for up to a 10-hour workday and a 40-hour workweek [NIOSH 1992].


ACGIH TLV

The American Conference of Governmental Industrial Hygienists (ACGIH) has assigned wood dust, all soft and hardwoods, except western red cedar a threshold limit value (TLV) of 1 mg/m(3) for certain hardwoods, such as beech and oak, and 5 mg/m(3) for soft wood, as TWAs for a normal 8-hour workday and a 40-hour workweek and a short-term exposure limit (STEL) of 10 mg/m(3) for soft wood, for periods not to exceed 15 minutes. Exposures at the STEL concentration should not be repeated more than four times a day and should be separated by intervals of at least 60 minutes [ACGIH 1994, p. 36].


Rationale for Limits

The NIOSH limit is based on the risk of pulmonary dysfunction and respiratory effects [NIOSH 1992].

The ACGIH limits are based on the risk of impaired nasal mucociliary function, potential nasal adenocarcinoma, and related hyperplasias (1 mg/m(3) TWA for hardwoods), and dermatitis and upper respiratory tract disease (for softwoods) [ACGIH 1991, pp. 1729-1730].

NIOSH is recommending a jet of pressurized air on sanding surfaces and router blades to dislodge material and improve the airflow of material. On some tables they recommend cloth covered chains as a curtain to the work surface. However, there don't appear to be any commercially available hoods that meet that criteria; cloth covered chains don't appear to be a


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## pintodeluxe (Sep 12, 2010)

ExElectrician,
Finally someone said what I was thinking. We spend all this time, effort and money to create DC systems that capture down to a fraction of a micron, when all we have to do is exaust it outside into a receptical. I live in the country where there are no neighbors or animals breathing the dust that may escape the container. 
Now I just need to come up with a receptical that my tractor can lift and dump in the compost pile.

I think we have missed the forrest for the trees. Er.. Uhhh… lumber.


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## DavidNJ (Dec 10, 2012)

Venting outside some form of particle separator and make up air. Makeup air is usually an intractable problem in cold climates or within residential structures (e.g. a basement).

If you live on a farm and work in a shed with a large opening outside, an outside exhaust should be fine. Most hobbyist woodworkers are in a garage or basement, and many of us are in climates where a large open door (it is under 10°F now) is not an option.


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## DavidNJ (Dec 10, 2012)

Update: The STEL is for a 15 minute period, not occurring more than once per hour or more than 4 times per day.

Note, on those that differentiate, they usually have the 1mg/m³ TWA for hardwoods and 5mg/m³ TWA for softwoods with a 10mg/m³ STEL.

Note: Mexican standards are more stringent than US standards.


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## DavidNJ (Dec 10, 2012)

I thought this article on makeup air was interesting: Makeup Air for Range Hoods . The author is describing the issues around makeup air for a 1200cfm range hood, roughly the same volume of air as a dust collector with an exterior exhaust. It isn't a pretty picture.

This is a vendor of makeup air systems: http://www.greenheck.com/products/detail/56


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## mbs (May 8, 2010)

I feel sorry for those that have to consider make-up-air. It adds significant complexity, takes up space, and is costly to implement.


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## DavidNJ (Dec 10, 2012)

The answer is to have the exhaust in the shop…what most home systems do.

Another article, a California Energy Commission design guide: http://www.energy.ca.gov/reports/2003-05-05_500-03-034F.PDF


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