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Shop Fox 1.5 HP (W1685) options for garage workshop

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Forum topic by Mengtian posted 12-12-2017 06:47 PM 1192 views 0 times favorited 16 replies Add to Favorites Watch
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Mengtian

12 posts in 38 days


12-12-2017 06:47 PM

I just purchased a W1685 Shop Fox 1.5HP DC. I run a one man shop and do not run more than one piece of equipment at a time. My main concerns are the tablesaw, miter saw, lather, planer (DW 735 w/the fan) and band saw.

All equipment would be within 20 ft of the DC.

I do not really want to move the DC around.

My plan is to use the Super Dust Deputy and vent the air into the attic or outside. Would it be sound to use 6 inch ducting for the main and then 5 for the branches and 4 going to the equipment?

Or best to make it mobile and move it around?

I plan on using blast gates and there would be one main line branching out 4 times over 20-25 ft. Each branch would be no more than 4 feet.


16 replies so far

View Mike_D_S's profile

Mike_D_S

382 posts in 2087 days


#1 posted 12-13-2017 04:42 AM

Well, you’re not going to like my answer maybe, but there is no shortcut here in my opinion to doing the math. I like the write up in the Grizzly cyclone manual (link below). Go to the designing your system part and read through it. Also, if you can find the performance curve for your DC that would be helpful.

Looking at the difference between static pressure loss between 6”, 5” and 4” hard pipe, I think the differences in static pressure drop would be lost in the noise of the entire system at the lengths you are worried about.

In a general sense, I think your collector is ok to draw through the 20 ft of straight hard pipe (in addition to the bends and branch), but the diameters matter. You say 6”, but you may find that you’re not keeping the velocity high enough in the 6” pipe. My general advice is if you are not using more than one piece of equipment at a time and for this kind of short run, then you should really think about why you would size up you main run bigger than the branch. Given the air restriction is at the inlet, then all you’re achieving is to slow the effective velocity of the chips/air when you go to bigger pipe diameters in your run (assuming you have enough CFM at the predicted pressure drop).

Especially if you are at a borderline CFM at the expected static pressure drop, using an upsized main branch could result in chip drop out in the main.

Mike

http://cdn0.grizzly.com/manuals/g0440_m.pdf

-- No honey, that's not new, I've had that forever......

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Mengtian

12 posts in 38 days


#2 posted 12-13-2017 10:30 AM

Thanks for your input. I have a 20 ft 4 inch hose and I might use that for a few tests. I still have a big shop vac with a dust deputy on it so in theory I already can do 2-3 machines at a time without moving things around. (The Shop Fox includes dual 4 inch ports if I decide to go that route.

My main concern is to have enough air movement by the time it gets to to the lathe. I can approximate that with the 20 foot 4 inch hose.

If I need to move the thing around, so be it. But if I can physically mount it and have the output go outside that is preferred.

View rwe2156's profile

rwe2156

2749 posts in 1353 days


#3 posted 12-13-2017 03:19 PM

I would definitely go with ducting even in a small shop. You will drive yourself crazy moving/connecting/disconnecting the DC every time you switch machines. I did that for a while ended up most of the time saying heck with it I have 1 board to plane, just sweep up shavings.

Yes, 6” main ducts as long as possible to machine, adapter to 4”, blast gate and 4” flex to machine.

Yes the lathe will be the most difficult to collect, so will the miter saw. You won’t approximate anything running 20’ of flex compared to a 6” duct w/ 3 or 4’ of flex – the latter will be far superior air flow.

My system is a Jet 1 1/2HP blower/SDD cyclone/6” PVC/exhaust outside it performs good enough for me.

-- Everything is a prototype thats why its one of a kind!!

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Mike_D_S

382 posts in 2087 days


#4 posted 12-13-2017 03:43 PM

As noted by rwe2156, 20 ft of 4” flex hose produces approx. 4 inches of static pressure loss, where 20 ft of 4” hard pipe is about 1.25 inches loss for a straight run. Adding bends, etc will increase both about the same. So you could easily find the 20 ft of 4” flex to be unacceptable while the 20 ft of hard pipe might be fine.

I’m not a DC purist by any means, so I’m not going to tell you that unless you put in a 5HP cyclone you’re wasting your time. But at the same time, I will tell you the 1.5HP Shop Fox is a lower power DC and therefore the difference between a happy DC user and an unhappy user will come down to the ductwork.

The W1685 is spec’ed at 1280 CFM at 0” static pressure loss and 10.1 inches max static pressure at 0 CFM. So assuming a sort of normal curve shape for a bag collector and with the fairly sure knowledge that the rated 1280 CFM is probably just for the blower, you might be looking at minimum acceptable performance (400 CFM) around 5 or 6 inches of static pressure.

So starting from max at 10.1, take off 1” for a seasoned bag, and then subtract 6” for your operating pressure target and that means your working pressure loss for your duct system is 3” static loss max.

If you are going to go through the effort to buy and install the ducting, you owe it to yourself to do the math on the longest run to make sure you are not wasting time and effort only to arrive at a setup that is not going to meet your desires.

Mike

-- No honey, that's not new, I've had that forever......

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Mike_D_S

382 posts in 2087 days


#5 posted 12-13-2017 03:46 PM

I’ll update my post above just to note that I added in the loss for a seasoned bag and I know the OP said dust deputy and maybe exhaust with no bag.

So while you may not have an inch of loss for a bag, you will get some loss for the SDD and the plumbing to hook it up unless you more or less scrap the stock W1685 setup and rebuild a direct flow setup from the SDD to the DC blower. So I’ll stand by my 1” of loss in either case for the moment.

Mike

-- No honey, that's not new, I've had that forever......

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Mengtian

12 posts in 38 days


#6 posted 12-13-2017 05:13 PM

Thanks for the replies guys. To clarify: my “goal” is to use a direct setup (meaning: main input to SDD to implerer to exhaust outside with no filter.

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Mike_D_S

382 posts in 2087 days


#7 posted 12-13-2017 08:31 PM

Go through the nice tutorial here on Oneida’s site on sizing duct work.

https://www.oneida-air.com/static.asp?htmltemplate=static/ductwork_tutorial01.html

The initial reaction is “I need 6” duct”. But go through it carefully, the math they did only applies for 6” all the way the machine (a 20” planer in this case, which is a high CFM application). As you add 4” branches, you starting increasing the static pressure losses, but also create a velocity change at the transition.

So if you want to maintain 3500 fpm in 4”, you need >300 cfm, but for the same 3500 fpm in 6”, you need >675 cfm. Since I doubt you’ll be able to deliver 675 CFM with your setup and ducting going to 4” branches, then you have some velocity loss that you’ll have to account for. So if you get 475 CFM effective, then your velocity in the 6” main will be down to 2420 FPM, which may be fine or might have some drop out.

But going with 5” duct gets you 3500 FPM at 475 CFM.

Just reinforcing that the “to equipment” part of your drawing above is likely to be the limiting factor and bears some actual design rather than just copying an existing layout.

Mike

-- No honey, that's not new, I've had that forever......

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Mengtian

12 posts in 38 days


#8 posted 12-14-2017 11:59 AM

OK, so, if I move the lathe closer and my longest main duct is 15 feet…Should 4, 5, or 6 inch main ducting be best?

View Knockonit's profile

Knockonit

218 posts in 75 days


#9 posted 12-14-2017 01:45 PM

Well, i have a penn state on wheels, i believe its 2 hp, or close to it.I move it from one machine to next, mostly because i no longer have a large shop thats dedicated.
On another note, i am picking up another unit almost identical as i have my drum sander, planer and jointer on the rear patio next to storage shed. all other tools, table saw, table top jointer, router table and sanding table are in garage, and of course both lathes are there, i have a mini jet and a larger HF.

I usually have the garage door open when in garage, so the absolute perfect air from DC is not required with the 20 ft hose it usually sets outside, ( of course it helps to live in a state that has sun and decent weather 355 days a year, so to speak).

When i h ad cabinet shop we had a monster 20 hp cyclone system, almost needed tie downs when next to the big machines, oh how i miss that shop.

anyway, it takes a whole lotta suck to pull over 40 lf of duct work even with blast gates,
be anxious to see final layout and implementation of solution.
good luck with it
Rj

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tomsteve

701 posts in 1092 days


#10 posted 12-14-2017 02:00 PM

“and vent the air into the attic or outside.”
attic,for some reason, seems like a really bad idea. if ya vent outside, youre going to need makeup air. youll be pulling quite a few CFM’s of air out of the shop every.well…minute.

when i was set up, i had that exact same unit with a 55 gallon seperator with a thein baffle. 26’ main run with drops for sanding station, router table, jointer/planer( had them side by side and easy to switch machines), TS, miter saw, and floor sweep. 6” mains up to blast gates, then 4” to the machines. it worked great for me. doesnt mean it got all dust, but it got most of it.

View JBrow's profile

JBrow

1311 posts in 793 days


#11 posted 12-14-2017 03:08 PM

Mengtian,

If it is possible, positioning the dust collector centrally among the machinery could reduce static pressure. For example if the dust collector was between the miter saw and drill press, the length of pipe on each leg would be cut about in half and therefore should improve air flow at the ends of the two branches.

That would lengthen the exhaust pipe. But since the dust in the exhaust is fine dust and would seem to remain suspended in the air better than large dust, 6” exhaust to the outdoors could have enough air flow to keep most of the fine dust from settling out.

View Mike_D_S's profile

Mike_D_S

382 posts in 2087 days


#12 posted 12-14-2017 03:48 PM

Ok, I did the maths…

First off, I found this from the Wood Magazine review article which included the W1685:

Then I did an overlay match to produce a matching fan curve.

Then I laid out a several size options for ducting using mixes of 4”, 5” and 6” following the basic guide image like in the Oneida tutorial with one 90 deg elbow at the tool and two 90 deg elbows to the cyclone. Cross referenced CFM against the fan curve plot and computed velocity in the main duct.

So you can review all those setups. All of them potentially work from a CFM perspective, but a few of them are certainly marginal to bad on velocity in the mains. A note on the math, I used published SP loss numbers for 3500 CFM from the Grizzly manual. Pressure loss is strongly related to flow velocity. So actually, the higher velocity in the 4” will actually increase pressure loss, so the actual CFM in the 4” might actually be slightly below 400 in the actual balanced system. On the contrary, reduced velocity in 5” and 6” cases would lower SP loss, raising effective CFM and velocity. So there needs to be a bit of judgement call, but you’re not going to go from 450 CFM to 600 CFM or from 2500 FPM to 3500 FPM. It becomes a question of how marginal the difference is.

Depending on what you are going to do exactly, you may never notice any problems. And if your heavier chip generators (jointer, planer, lathe, etc) are close to the DC it’ll be more in your favor.

If It were me, I’d go for the 5” branch and mains options followed by 4” branch with 5” mains and try to bring down the SP losses some. Doing things like allowing a longer lead in to the cyclone by using two 45 deg elbows and a longer straight transition run, changing the tools to all have 5” ports if possible, etc should all help to bring down the SP losses slightly. But in all cases, I’d avoid 6” mains as you just don’t have the power to keep the velocity up.

Regards,
Mike

-- No honey, that's not new, I've had that forever......

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Mengtian

12 posts in 38 days


#13 posted 12-14-2017 07:21 PM

Thanks a lot Mike! That is close to what I calculated using a few other sources.

Things in my favor:
1: My planer is a DW735 with the blower built in. I normally keep this near the door and just toss out the 4” hose and let it blow outside. Not sure if i will even hook up the planer.

2: Table saw is going to be 5 feet from the DC. The table saw and lather are my biggest concerns followed by the miter saw. I am going to move the lathe closer.

3: I have a Porter Cable 36” jointer with a 2 inch inlet. I will use my shop vac for this.

I think I will go with 5 inch and see how it goes.

View Mike_D_S's profile

Mike_D_S

382 posts in 2087 days


#14 posted 12-15-2017 03:42 AM

Lathe dust collection is a two part story for me. I have a big plexiglass hood that I use as a small particle collector essentially open sided box that I pull up close to the back of the lathe. The ribbing and chips tend to just end up on the ground and I either sweep or vacuum them up later.

I think the 5” setup is probably a good middle ground.

Mike

-- No honey, that's not new, I've had that forever......

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Mengtian

12 posts in 38 days


#15 posted 12-17-2017 01:14 PM



“and vent the air into the attic or outside.”
attic,for some reason, seems like a really bad idea. if ya vent outside, youre going to need makeup air. youll be pulling quite a few CFM s of air out of the shop every.well…minute.

when i was set up, i had that exact same unit with a 55 gallon seperator with a thein baffle. 26 main run with drops for sanding station, router table, jointer/planer( had them side by side and easy to switch machines), TS, miter saw, and floor sweep. 6” mains up to blast gates, then 4” to the machines. it worked great for me. doesnt mean it got all dust, but it got most of it.

- tomsteve


Let me clarify the attic comment. I meant that I would have the output go up to the attic and out one of the under the eave vents.

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