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Forum topic by jgt1942 posted 05-22-2016 09:03 AM 1312 views 0 times favorited 36 replies Add to Favorites Watch
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jgt1942

137 posts in 1354 days


05-22-2016 09:03 AM

Topic tags/keywords: air cleaner dust collection dust collector lathe turning

Lately I’ve been turning very dry Mesquite and it has generated a LOT of DUST! The entire shop (2-car garage) has dust on everything. Thus I decided it was time to try and resolve this issue. Currently the lathe dust is my major issue. BTW when sanding a turned piece very fine dust is created. I have another project on the list to help with this.
My first thought is to put a curtain around the lathe area. In the following image the view is looking down directly over the lathe.

I’m going to run a 12’ piece of 3/4” conduit from point A and B 6’ out, bend 90 degrees and then go toward the center of the area. At the center I will have about 1’ overlap. The pipe will be hanging from the 10’ ceiling. The curtain, clear HD plastic will slide along the pipe thus I can push each side toward point A & B when the lathe is not being used. The pipe will be attached to the wall at point A & B, at the bend I’ll have a bracket that attaches to the inside of the bend (this is the current plan) and then to the ceiling and at the end of the pipe where they overlap I’ll have a rigid mount to the ceiling. Thus the pipe will be hanging about 3-6” from the ceiling.
The hooks for the curtain will look something like the following.

At this time I have not decided on the plastic for the curtain or how close it will come to the floor. Any thoughts?
Basically when the curtain is closed the area will be about 6’ x 11” or 66 SQ FT If I multiply by 10 (the ceiling height) I have about 660 cubic feet.

Obviously I need something to clean the air in this area. When turning I do wear my Trend Airshield and per Trend the filters are good for 0.6 microns. Thus I’m reasonably safe but I want better and the curtain will go a long way to contain the dust and turnings to this area but not clean the air in the area.

I did a reasonable amount of research and very quickly realized that if I want a really good air cleaner it was going to cost a lot! One quote was $2500. Cost for me is a major issue.

I’ve look at simple box fans with HEPA filters (MERV 13-15) and this is a quick simple solution and would be as good as the $2500 system but I wanted to step it up a bit. So I picked up a couple of furnace blowers from a local HVAC shop. He was happy to just give them to me and I was like a kid in a candy shop that was just told I could have anything I wanted.

As soon as I got home I tested both units, they worked on all three speeds and measured one of the identical units.

My first thought was to install each blower in a box similar to the following.

I then looked at the Bill Pentz and saw what he did using the Wynn Nano filter. Note he is pulling the air through the filter.

And I thought, why not use the furnace blower with a Wynn filter as follows

BTW this unit will be mounted above the door near point A.
Finally the question, I’m looking for suggestions and need your feedback

I’ve thought of some different designs
1) mount the assembly using a metal frame to hold the blower assembly and filter. Obviously I need some form of adaptor to connect the filter to the blower and need to block off one side of the squirrel cage. If blocked off I don’t know what this would do to the air flow.
2) mount the blower assembly in a box and attach the filter to the box. This would not require blocking off one side of the squirrel cage.
3) If I mount the unit where the blower was near the back wall and the filter near the bend in the pipe, this would force the air exiting to blow along the back wall forcing circulation in the area when the curtain is closed. If the curtain is open then the air would go along the wall, hit the door on the right (BTW behind the door is my air compressor) and then just wrap out into the shop.

Currently I have no idea what the CFM of the blowers are, again they are 3 speed and all three speeds work. They do start to get a bit loud as the speed goes up. I’ll have to measure and see what the actual levels are. Possibly if the blower assembly is in a box, it would reduce the noise a bit.

I don’t know what sound proofing I could install that would reduce the noise.
I don’t know what speed I need to run the blower at to get the air cleaned.

BTW I will be on the road a couple of weeks thus my internet access will be hit and miss until I return home.

-- JohnT


36 replies so far

View ClammyBallz's profile

ClammyBallz

309 posts in 602 days


#1 posted 05-22-2016 12:59 PM

What’s the HP on the motor? You can usually get a cfm range from that.

View TraylorPark's profile

TraylorPark

151 posts in 1064 days


#2 posted 05-22-2016 01:51 PM

I can tell you that one of those units will easily clean the air in your shielded area, and both will get the whole shop done. I have one furnace blower in my shop, 20×20, and when I got it set up I tested it by turning the leaf blower on inside the shop to get as much dust in the air as possible. For the test I had the air cleaner exhausting out the back door, because that’s how I use it in the summer. Before I turned on the air cleaner I had dust so thick in the air it looked like a Smokey Mountain Morning, and within 3 minutes that air was clean as could be. The results drop a little when the filters are on and recirculating the air within the shop, but it still works great, maybe about 10 minutes on dirty filters to get the air scrubbed.

-- --Zach

View Wondermutt's profile

Wondermutt

69 posts in 322 days


#3 posted 05-22-2016 02:48 PM

I can’t help you with the cfm, but I did the same thing with a plastic divider between the wood production area and the finishing area. With that make sure you get sheeting that is static proff. What I mean is that if you use a poly that does not have esd protection, you will have issues with the dust collecting on the curtain and constant static discharge akin to dragging your feet across the floor and touching a door handle.

I ordered mine from a welding supply house .

I have two of the filter units like you are trying to build and they work great for my 40×80 ft shop. I did not use the Wynn filter but instead hepa and prefilters that can be sourced from the home center. I have to replace the prefilters every week and the hepa about once a month.

Good luck

WM

View bigJohninvegas's profile

bigJohninvegas

215 posts in 927 days


#4 posted 05-22-2016 04:04 PM

The curtain really isn’t necessary if you are going to get or build an air cleaner.
I am using a home built air cleaner, and all my friends have store bought versions.
Mine is a single speed with a timer switch, and works just as well as the store models.


I don’t have the specs on my blower motor, but I believe it is a bit smaller than what you have pictured, and this little air cleaner keeps my 3 car garage/shop spotless. Even when I forget to turn it on and it gets a little cloudy in here. Hit the switch and within a couple minutes it’s clean clear air.
Here is a link to a project by OldKranky. He has a link to the same plans I used to build mine.
http://lumberjocks.com/projects/59540 I used a standard filter size that also matches the jet and PM filters. I think 12X20 range. I had planned to buy the washable filter that the jet uses, but both cost of that filter, and seeing how well the 3 filter system worked. I have left it as the plans intended.
Good luck

-- John

View clin's profile

clin

514 posts in 462 days


#5 posted 05-22-2016 04:50 PM

I agree that one of the blowers shown is likely large enough to do your whole shop. But no air cleaner will keep a shop free of dust. Away from the cleaner, the air speeds are slow enough that the dust can still settle out. And there are always eddies and dead spots with little air movement.

Unless you’re going to have the equivalent of a leaf blower blasting all the surfaces (keeping the air stirred up), no single air cleaner is going to get all the dust. So I still think your curtain has merit for containing the dust.

Keep in mind that this curtain doesn’t need to be plastic or air tight. With little pressure from one side to the other, there will be very little air movement through it, so even a basic fabric would work fine.

I key thing about these cleaners is to have the intake as near the dust source as possible. Again, because the air speeds slow considerable just a few feet from the filter.

As to the filter itself, the one you show from Bill Pentz is not a shop filter, but one he uses in his house (I think). Therefore it is only exposed to fine dust and is not a bulk filter. I think these fine filters are best used as a second stage filter.

I’ve seen some examples where people make (or modify) a room filter using common furnace filters on the intake side, and a Wynn on the exhaust side. That way the Wynn doesn’t get clogged with large dust particles, that a cheap filter can easily trap. I think the experience was the Wynn might rarely need cleaning (yearly or less).

I have a Jet room filter, and this is something I’m thinking I might do someday.

-- Clin

View jgt1942's profile

jgt1942

137 posts in 1354 days


#6 posted 05-22-2016 06:00 PM

WOW what great feedback. I’m still up in the air (no pun intended) as to the traditional box or the Bill Pentz method.

Regarding the traditional box, why hang it from the ceiling? Why not just mount it to the ceiling? Vibrations should not be an issue after all when the blower is installed in the furnace it is mounted to the furnace which is mounted to the house frame.

I loosened one of the motors and confirmed that it is 1/2 HP, I’ll assume the other is the same. AMPS 7.3, RPM 1075/4 speed (I only tested three speeds) Model K55HXENV-0115.

I have an app on my phone to measure the dB level and for this test this is good enough. I do have a separate mic that is better but I did not use it. Following are my results.

Regarding the curtain, I need it for two reasons
1) Keep all/major portion of the dust and turnings in the area of the lathe. Currently after a turning session I will have dust and pieces of wood 25 feet away toward the garage doors on the opposite end of the shop. I’m often turning tree branches/trunks with the bark on the wood. Often the bark becomes loose and goes flying.
2) Stop flying objects from flying across the shop. More times than I care to admit I will get a catch and the wood goes flying. I recently had a 12” platter I was working on break into 9 pieces and some made it all the was to the front of the garage (my lathe is in the back right corner of my garage/shop). Also sometime when a crack is uncovered this will cause the wood to break and fly.

I’m really impressed by the cleanness some of you have reported, this is very encouraging. In one of the other thread I saw last night it was suggested to use a flashlight at night with the DC running to see how much dust was in the beam of the flashlight. It is MUCH easier to see the dust using this method. Following is my post in the thread (see the entire thread at http://lumberjocks.com/topics/49041#reply-2744578)

This seems like a really good idea. It is now 0034 hours and I gave it a try. Before I turned on my DC I used the flashlight to see if any dust was moving in the air and could see none. When I first turned on the DC immediately I could see dust in the light beam and then I noticed that there was a lot of air coming from the motor on the DC and then realized that air was being drawing through the motor for cooling. I then concentrated on the top bag and could see a very small amount of dust in the beam, however I’m not sure if the dust was from the bag or the air going through the motor.
I do have a Thien baffle (Tophat) that removes about 96% of whatever is going through it. The air then goes through the DC impeller and then into the bag. Because I also turn wood and have been turning very dry Mesquite my shop is covered with dust. I’m in the process of trying to determine what I want to do for an air cleaner. **
Obviously I will use this simple test as I move forward with the air cleaners. Because I have two blowers and almost 1,000 sq feet in the shop I will use both.

-- JohnT

View clin's profile

clin

514 posts in 462 days


#7 posted 05-22-2016 09:14 PM



I m really impressed by the cleanness some of you have reported, this is very encouraging.
- jgt1942

I would temper your expectations as far as how clean this will keep your shop. I think people have very different ideas of what clean means. I run my Jet filter anytime I’m making dust and often when I’m simply in the shop. As moving around the shop kicks up dust. However, I have a black tool chest, and it clearly shows a build up on it.

My shop is also small at about 300 sq ft, so it’s not like the filter is trying to work a large area.

However, while they won’t get it all, I think they are a great idea. But I see them as sort of 50/50 as far as cleaning the air from a specific dust event vs keeping the air clean by constantly running it.

Keep in mind that in clean rooms (like where they make computer chips), they don’t just clean the air and call it good, they are running filtered air through the rooms non-stop. And in those cases, virtually the entire ceiling is incoming clean air and the entire floor the exhaust vent for the room.

We of course are not trying to get to those levels of clean, but the same principles apply.

Here’s a link to a Stumpy Nubs video showing how he converted his Jet room filter to use a Wynn.

https://www.youtube.com/watch?feature=player_embedded&v=iR6P7VV2DUY

-- Clin

View ClammyBallz's profile

ClammyBallz

309 posts in 602 days


#8 posted 05-22-2016 09:36 PM

You’re gonna have to put the blower in a box. It pulls air from both sides and will not work like you anticipate. The pentz design you show is using an inline duct fan, not a squirrel cage blower like you have.

View jgt1942's profile

jgt1942

137 posts in 1354 days


#9 posted 05-22-2016 10:30 PM



You re gonna have to put the blower in a box. It pulls air from both sides and will not work like you anticipate. The pentz design you show is using an inline duct fan, not a squirrel cage blower like you have.

- ClammyBallz


This was as I suspected, thanks for the confirmation.

Here’s a link to a Stumpy Nubs video showing how he converted his Jet room filter to use a Wynn.
—Clin

Much thanks for the link. In the link you provided Stumpy provided a link for all of his dust collection videos and such. Tons of great info.
http://www.stumpynubs.com/dust.html

At this time I’ve decided to
1) box the furnace blower as suggested by ClammyBallz
2) use the Wynn 9L300NANO or equivalent. I got a great price ($124) for the 35A274NANO replacement from https://damnfilters.com/, Jim Orr is the person I’ve been communicating with. The 9L300NANO will be a bit easier to adapt to my furnace blower.

I’m now sorry that I will be going out of town for a couple of weeks and when I come back I have company coming thus it will be a few weeks before I can really tackle the project but in the mean time I can work on the ideas.
I just copied my Dust Collection folder (all 11 GB) from my network drive to my laptop which is going with me. This will allow me to work on things design wise while I’m on the road, time permitting.

-- JohnT

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jgt1942

137 posts in 1354 days


#10 posted 05-25-2016 05:57 AM

Based on the feedback in this thread and other research I’ve created a concept drawing. When I get back home I’ll discuss with my welder friend and see what he thinks about the metal support.

Starting on the left (current thoughts)
a) I need to close off the opening to force air to enter via the filter. For lack of a better term I’ll call this the sealing plate. Not shown is a seal that will be between the wood/metal that will seal the opening closed. Also I’ve not identified how this will be mounted to the filter (more on this below)
b) Is the replacement filter for the Wynn 9L300NANO. Not shown is the seal between the filter and the box on the right. The size of the hole in the box will be the diameter of the opening in the filter, approx 8.5”
c) Is angle iron that the filter will rest on. Possibly I’ll have two pieces on the top in a similar fashion. I could also make some metal rings (inside diameter larger than the filter at least on the left end. The seal on this end could be attached to the metal ring. Also the sealing plate could have two eye-bolts that are attached to the ceiling to help support the weight of the unit.
d) The box that will hold the blower assembly. On each side of the blower currently I’m thinking of leaving about 6” of space between the blower and side of the box thus allowing the air from the filter to easily enter the squirrel cage. The hole in the box where the end of the filter meets the box will be the ID of the filter (or slightly larger), approx 8.5”. Also on the outside of the box where the filter meets the box I need either a metal ring or metal plate that the angle iron can be welded to. This plate will be secured to the box.
The distance between the filter end and the back of the blower is about 7 3/4”. I’m assuming that this is enough. It would be very easy to add more space. The overall length from the sealing plate to where the air exits the blower box is about 5’ and the area I’m inserting the unit is about 11’ long. I’m currently thinking of running the unit parallel to the back wall where the filter will be over the glass exit door are and the air will blow toward the door to the air compressor. I’m thinking I want the right side of the unit closer to the compressor door and I want to keep the filter over the glass door. However I need about 3’ of space between the sealing plate and the curtain on the left side. For filter cleaning and filter replacement I need about 3’. I could also make the angle iron supports a bit shorter.
e) This is my actual blower (see the image in the initial post)

To clean/replace the filter
1) remove the sealing plate
2) slip a plastic bag over the filter all the way up to the box
3) gently slide the filter away from the box and hold the bag closed. The angle iron will prevent closing the bag fully at this time
4) slide the filter and bag off of the angle iron. Because the angle iron is providing support for the filter it should slide. At some point the filter will tip completely into the bag and care must be taken to try and close the bag. At this time I’m standing on a ladder, it would be safer to use one of my movable tables to provide more secure footing.
5) The filter is now in the bag, take it outside, gently set it on the ground and remove the bag
6) Using an air compressor with a long blower pipe blow clean the filter. It will not be possible to get all of the dust out of the filter but do the best possible. Blow air on the outside of the filter as well as the inside. When blowing the inside of the filter the blower pipe should be fitted with a 90 degree tip.
7) after the filter is cleaned (air only, DO NOT use water) reinstall the filter.
7)

-- JohnT

View clin's profile

clin

514 posts in 462 days


#11 posted 05-25-2016 05:08 PM

I question putting the fine filter on the intake. Ambient room filters collect a lot of dust and need cleaning relatively often. If you have a two stage filter, you’ll still have to clean the first stage as often, but you can use a less expensive filter for that, and leave the expensive fine filter to do only what it needs to do.

Also, I don’t care how careful you are, cleaning any filter is going to put wear and tear on it. So again, another reason to limit what the expensive, fine filter collects.

You’ve seen the example in the Stumpy Nubs video, of a common furnace filter on the input and a fine filter on the output. The blower isn’t going to be affected very much by air carrying fine dust.

That’s the way I’d approach it unless there was a compelling reason not to do it that way.

-- Clin

View ClammyBallz's profile

ClammyBallz

309 posts in 602 days


#12 posted 05-25-2016 05:56 PM

It would be fine if he boxed it in and put furnace filters on the sides. But it seems like a lot of effort when you could use the bag filters for much less money and build it like a jet or delta air filter.
http://wynnenv.com/products-page/ambient-filter-pricing/122412vb/

You could mount 2 of the bags in a 2’x2’ box and easily swap them out in 10 seconds when you need to replace them. Merv 8 furnace filters from ace are $5, you layer those in there and the main bags won’t need to be replaced as often.

View jgt1942's profile

jgt1942

137 posts in 1354 days


#13 posted 05-26-2016 01:30 AM

If I understand the rating correctly the problem with the http://wynnenv.com/products-page/ambient-filter-pricing/122412vb/ filter is that it will pass a 1 micron particle and the filter is about a MERV 6-8, I want to stop particles as small as 0.3 microns this is a MERV of 15-16. The suggested WYNN filter has about 16 sq feet of area where as the filter I’m considering has almost 300 sq feet. Thus there is a huge difference in performance where the filter I’m considering is much better. Also with the larger capacity I can push more air through the larger (and more expensive) filter. Via the source I mentioned above I expect to pay about $125 for the filter vs $70 for the suggested WYNN.

The suggested MERV 8 filters from ACE do not meet my MERV 15-16 requirement.
Possibly I have misunderstood the spec sheets I’ve been looking at.

-- JohnT

View jgt1942's profile

jgt1942

137 posts in 1354 days


#14 posted 05-26-2016 05:03 AM



I question putting the fine filter on the intake. Ambient room filters collect a lot of dust and need cleaning relatively often. If you have a two stage filter, you ll still have to clean the first stage as often, but you can use a less expensive filter for that, and leave the expensive fine filter to do only what it needs to do.

Also, I don t care how careful you are, cleaning any filter is going to put wear and tear on it. So again, another reason to limit what the expensive, fine filter collects.

You ve seen the example in the Stumpy Nubs video, of a common furnace filter on the input and a fine filter on the output. The blower isn t going to be affected very much by air carrying fine dust.

That s the way I d approach it unless there was a compelling reason not to do it that way.

- clin


Clin, I’m attempting to follow the advice given by Bill Penz, see http://billpentz.com/woodworking/cyclone/air_cleaner.cfm
I really want to capture the “fine” dust, e.g. down to 0.3 microns. Fir this level I need a filter with a MERV 15-16 rating. In my research I did not find any box type filters that had a MERV 15-16 rating and none had 300 sq feet of filter area.

Bill has a LOT of information on his site and because of health issues caused by dust has spent a lot of time researching, testing and refining how to properly eliminate the dust in his shop and house. In his test he does mention that at first he positioned the blower to blow air into the filter but got better results when he pulled the air through the filter.

For me the filter will be 99% (I’m estimating about $125 via my source, see previous post in this thread) of the cost and I expect for the filter to last several years.

Currently while turning I use a Trend Air Shield Pro helmet and per Trend this will remove particles as small as 0.6 microns. Sometimes I even use the helmet when using my 6×48 belt sander which generates a LOT of dust. Dust collection for this is another up coming project. My palm sander is the Mirka Ceros sander and has its’ own dust collection system. BTW I highly recommend this system. I also have a hood behind my lathe which I currently connect to the shop DC but it is not very effective when sanding pieces on the lathe. I have another project in mind that will resolve this problem area but it will be a few months before I can get to it.

-- JohnT

View clin's profile

clin

514 posts in 462 days


#15 posted 05-26-2016 05:41 AM



Clin, I m attempting to follow the advice given by Bill Penz, see http://billpentz.com/woodworking/cyclone/air_cleaner.cfm
I really want to capture the “fine” dust, e.g. down to 0.3 microns. Fir this level I need a filter with a MERV 15-16 rating. In my research I did not find any box type filters that had a MERV 15-16 rating and none had 300 sq feet of filter area.

- jgt1942

I’m just saying to move your fine, cylindrical filter from the intake to the exhaust side. And then add a furnace filter on the intake side. The way Stumpy Nubs shows in his video. You just transition from the rectangular output of the blower back to a round duct and then add appropriate flanges to mate the fine filter.

And I agree completely with getting down to sub-micron level.

Also, doing the DIY box means you can size the box to handle common furnace filter sizes and you could put one on up to 5 of the six sides of the box (all but the exhaust side). I don’t think you probably want that many, but certainly using 2 or 3 sides of the box, for intake, would make sense. The larger the area the better.

-- Clin

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