Question about my convolulted dust control ductwork

[Frank Pellow]

Attached is a picture of some of the ductwork for my dust controller. Everything is just temporarily in place.

There is one part of it that seems very convoluted to me and I am wondering if someone can suggest a better arrangement. Notice that immediately after taking the 7" pipe up to the ceiling I have a drop with 5" pipe that twists around then down the wall where it terminates with a blast gate. I will eventually connect a jointer to the underside of the blast gate with a flex hose.

[Steve Cox]

Why don't you take the straight section that the 45 is on and put that coming straight out of the cyclone and then put the elbow and section going up on after that? It keeps the duct low for few feet but would be much easier to hook up the jointer in addition to making the whole system more efficient by keeping the run straight for a few feet into the cyclone.

[Frank Pellow]

Why don't you take the straight section that the 45 is on and put that coming straight out of the cyclone and then put the elbow and section going up on after that? It keeps the duct low for few feet but would be much easier to hook up the jointer in addition to making the whole system more efficient by keeping the run straight for a few feet into the cyclone.
I thought about doing something along those lines and that is why I posted the question. However, everything I have seen from Oneida immediately takes the 7" pipe up to the ceiling with no joints along the way. So, I thought that that might be a "sort of" recommendation. I have sent the picture to the Canadian distributor for Oneida and am awaiting their response.

[Steve Cox]

I have seen that on almost every cyclone setup too but Bill Pentz on his website says that keeping the run straight for about 5' before it gets to the cyclone improves efficiency markedly. I also have read Bill's comments about Oneida's duct design and he doesn't like it so take from that what you will:o .

[Chris Padilla]

Frank,

Can you mount the cyclone any higher? I would get that motor nearly scraping the ceiling if possible...maybe even through it if it makes any sense.... I think that 90 at the inlet will cut a lot of effciency out of your system.

You really want to strive for a nice long straight unobstructed (no 90s, no tapers, no bends, no off-shoots) shot from the cyclone to the first branch. Steve mentions that Bill likes to see 5'...that seems fine...a good rule of thumb so to speak.

For your main feed (and I'm not considering any branches...yet....):
I would move the cyclone up high enough such that you can run straight from the inlet, 90 around the corner and run the pipe just above the window. This removes 1 90 turn from the first couple feet to the inlet for you. I think a 90 bend is like the equivalent of 5-6' of straight pipe. Go along the top of the window and then 90 out to the center of the shop where hopefully you can use some 45s and no more 90s.

For the branch near the window (your jointer hook-up), perhaps you can put that to the right of the window? However, left seems to make the most sense but it puts the wye closer to the inlet.

Anyway, some food for thought.

[Steve Clardy]

I'd say do what they others suggest Frank. Move the cyclone up.
Sure glad all my duct is in the floor. No piping to deal with. Just a flex going to the inlets on the floor.:rolleyes:;)

[Steve Cox]

Frank,

It looks like your ducting goes to the ceiling only to come down again very soon. Why not take Chris' suggestion and mount the cyclone as high as you can and then make a straight run from the cyclone to where it drops off the ceiling again. It should help with the jointer run plus eliminating a couple of elbows.

[Jim Becker]

One of the reasons you're having a time of it is because of the fixed angle elbows...they don't let you play with the angles to get the most efficient route. You can't do gentle curves with fixed angle components.

The big 7" 90º elbow (top center of the picture) that is almost immediately followed by a reducer is a prime example. I would have used a 7" adjustable elbow with just a gentle curve down followed by a LONG reducer (not the short/abrupt one show) and then an adjustable elbow in the smaller size to branch off closer to the ceiling/beam. Seeing things as they are now, I might have come off the cyclone with a 7-5-7 lateral with an adjustable elbow to go up-top. This brings the 5" drop straight out off the lateral while still continuing the 7" run to the ceiling. In an ideal situation, you would have been able to have a couple feet of straight pipe before that branch, but you don't have the space. In the sum of things, you have a kick-butt cyclone and your overall performance will not be noticably hurt no matter how you do this in your size shop, but the smoother you can make things the happier you will be.

BTW, have you considered putting strain-reliefs on those electrical drops?

[Frank Pellow]

Chris, Steve, and Steve, I really don't have the nerve to ask the guys (Emrys and Bert) who helped my to mount the unit back again to re-mount it. :( And, I don't want to ask someone else because Emrys and Bert will both be in my shop in the future and would notice the change. So, the unit will stay where it is.

Chris, I really don't need any duct work over near the window. Most of the ducting is needed on the same side of the big beam as the dust controller.

Jim, I did not even know that the parts your describe existed and I think that it is too late now for me to trade in what I have and get that stuff. I wish that I had had you rather than Oneida/Welbeck as my consultants. :D

Unless I hear some good reason not to do so, I think that I will make a change as per Steve Cox's original suggestion. :)

Jim, there is about 20 centimetres of what I regard as strain relief at the top of each of the 6 electrical drops. What exactly did you have in mind? :confused:

[Jim Becker]

Jim, I did not even know that the parts your describe existed and I think that it is too late now for me to trade in what I have and get that stuff. I wish that I had had you rather than Oneida/Welbeck as my consultants.
I'm surprised that the duct was spec'ed out that way. Actually, I'm surprised that spiral duct and welded elbows were provisioned...Oneida pretty much puts 24 guage snap-lock and adjustable elbows for home shop designs unless otherwise asked. Perhaps this was a Welback thing...


Jim, there is about 20 centimetres of what I regard as strain relief at the top of each of the 6 electrical drops. What exactly did you have in mind?
Sorry...I could not see any strain relief in the photos. What I was anticipating was the wire mesh strain relief that tightens around the cable when stress is put on it.

[Tyler Howell]

Go ahead and ask them! Tell them it's a pix police order. They'll cuss you out then fix it.

[Tom LaRussa]

Frank,

Given that you're not going to move the cyclone up toward the ceiling, here is my suggestion, in graphical form:

[Jim Becker]

My thoughts exactly, Tom... :D

[Frank Pellow]

I'm surprised that the duct was spec'ed out that way. Actually, I'm surprised that spiral duct and welded elbows were provisioned...Oneida pretty much puts 24 guage snap-lock and adjustable elbows for home shop designs unless otherwise asked. Perhaps this was a Welback thing... . The design was a combined Oneida/Welbeck thing so I don't know who was responsible for suggesting just what.




Sorry...I could not see any strain relief in the photos. What I was anticipating was the wire mesh strain relief that tightens around the cable when stress is put on it. The strain relief projecting out of each box for about 20 cetimetres is a wire mesh so I guess I have what you recommended.

[Frank Pellow]

Frank,
Given that you're not going to move the cyclone up toward the ceiling, here is my suggestion, in graphical form:

Hey Tom, that a great way to show your suggestion. On top of that, it looks like a couple of good simplifications. I will need to echange some fittings with the supplier (Welbeck Sawmill) but I think that they will be ammenable to that.

[Chris Padilla]

Frank,

Supply us with the names/email address of your buddies and we'll convince them that the right thing to do is to help you move that cyclone up higher! :D

I think it is KEY to have the inlet into the cyclone be as straight as possible. Moving up the cyclone, you can probably get away with using 2 45s to get the ducting near the ceiling if not just a straight shot of pipe.

In the end, what you have and with Tom's improvments, you will probably be fine and until you change it like we suggested, you won't know what you are missing (maybe nothing? :) ). Perhaps in the future as funds become available, you can look into improvements to your DC if you find it lacking somewhat.

[Frank Pellow]

Thanks Chris. I know now that the best thing to do would be to move the unit higher but I am not going to do it. As you say, maybe later ...

Bt the way I just noticed the quote "Crown Molding: cut, cope, cuss, caulk.... " at the bottom of your post and I really like it. Is it new or have I just not noticed it before?

[Chris Padilla]

The signature quote is pretty recent...I heard it from another guy a couple weeks ago although he added "...beer..." to the end of it! :)

[Frank Pellow]

The signature quote is pretty recent...I heard it from another guy a couple weeks ago although he added "...beer..." to the end of it! :)
'Beer' doesn't work because of the initial letter. Now, in my case, my second favourite beer (next the draft Guiness, of course) is Creemore Lager. So I can add 'Creemore' to the end of the quote when I use it (and I will) -but that modified quote will only work for folks in Southern Ontario.

[Frank Pellow]

I have re-done this portion of the ductwork along the lines of what was suggested by Steve Cox and Tom LaRussa. Thanks Steve and Tom!

This looks a lot better and will not beg questions from people the way that I am sure the old arrangement would have done.

Other than looking better and save a lot of pipe, this gives me a 32" straight run into the dust controller. This isn't the 5' that Steve told was desireable, but it is better than the 6" in the previous arrangement.

A picture of the new arrangement is attached.

By the way Tom, that's a copy of the marked up photo that you posted nailed to the wall.

[Steve Cox]

That looks MUCH better Frank! Glad I could help in some small way. I'll be looking for return suggestions in a few months when I start my ducting:) .

[Jim Becker]

MUCH better, Frank. And not really too intrusive since the horizontal pipe and elbow are up high enough to clear machinery.

[Jim Dunn]

Sorry I didn't read all the post's in this thread I see you have addressed the strain reliefs. :o

Frank, you still haven't addressed Jim's concern about the cords not having strain reliefs. They Look like chinese finger "hand" cuffs. The are held in place with a nut on one end.
Their purpose is to put the strain of the cord hanging from the ceiling directly to the box mounted in the ceiling, not on the cord it's self or the wire connections. Their kind of expensive as the last one I bought was about $25.00 US but should be available in most full service electrical houses

(Wish I were more computer proficient I could probably dig up a link some where but I don't know how to post these things.)

[Frank Pellow]

Sorry I didn't read all the post's in this thread I see you have addressed the strain reliefs. :o

Frank, you still haven't addressed Jim's concern about the cords not having strain reliefs. They Look like chinese finger "hand" cuffs. The are held in place with a nut on one end.
Their purpose is to put the strain of the cord hanging from the ceiling directly to the box mounted in the ceiling, not on the cord it's self or the wire connections. Their kind of expensive as the last one I bought was about $25.00 US but should be available in most full service electrical houses

(Wish I were more computer proficient I could probably dig up a link some where but I don't know how to post these things.)
Jim, I think that I have addressed his concern. Attached is a close-up picture of what I have at the top of all six of my drop cords. To me, it sounds exactly like what you are talking about.

[Frank Pellow]

Jim, I re-read your post and see now that you now realize that I do have OK strain reliefs. But, I will not delete the post with the picture from the thread becuase it does show quite well what we are all talking about.

[Chris Padilla]

DC looks better, Frank! I think you'll be just fine.

[Jim Dunn]

Sorry Frank, I jumped before I looked (do that a lot). You should try to make them tighter as it looks like any downward pressure will go to the connections before the strain relief grabs tight. Just my 2cnts. How expensive were those strain relief you used if I may ask?

Merry Christmas

[Frank Pellow]

I finally heard from Welbeck Sawmill. Here is what they said:


Oneida really pushes 2' of straight duct right out of the cyclone before
any elbows or wyes. Apparently not adhering to that rule causes
more than normal turbulence within the cyclone which leads to more
particulate ending up in your filter. Bottom line . . . you end up cleaning
your filter more often because more dust than normal gets through the
cyclone.
It seems that I was already breaking this rule with the design Welbeck gave me (6" before an elbow). Now I am better (18" before a wye) but the rule is still being broken. :( I might manage to gain another couple of inches when I "permanently" mount the pipe, but that is the only further change that I plan to make.

[Frank Pellow]

Sorry Frank, I jumped before I looked (do that a lot). You should try to make them tighter as it looks like any downward pressure will go to the connections before the strain relief grabs tight. Just my 2cnts. How expensive were those strain relief you used if I may ask?

Merry Christmas
It must be an optical illusion. The strain relief is really really tight on the wires.

I don't recall the exact cost, but I think they were about $7 (Cdn) each.

[Jim Dunn]

That's dirt cheap for those strain relief units. I needed one and like I said I paid about $25 US. It's stainless steel and that may account for the price diff. or i got scr_wed.

Merry Christmas
Jim

[Jim Becker]

Frank, your lateral will "count" relative to the inlet distance for the straight run, so I think you are fine. The one thing I'd suggest you try and do is extend it "just a little more so that your drop can come off horizontally, rather than vertically as it is now. That will reduce the turbulence and the "collection" of stuff in the drop from other areas of the shop. It's always a good practice to make all drops come off the main horizontally for this reason whenever possible to do so.

[Frank Pellow]

Frank, your lateral will "count" relative to the inlet distance for the straight run, so I think you are fine. The one thing I'd suggest you try and do is extend it "just a little more so that your drop can come off horizontally, rather than vertically as it is now. That will reduce the turbulence and the "collection" of stuff in the drop from other areas of the shop. It's always a good practice to make all drops come off the main horizontally for this reason whenever possible to do so.
I didn't know about the horizontal preference, Jim. Thanks for the tip, and I will see if I can implement your suggestion.