Ducting Problem

[Burt Alcantara]

How do I connect the elbow to the ducting? I can connect either end of the elbow to either end of the duct. All ducting is 6".



http://www.spotsup.com/etc/photos/metal-90.jpg

http://www.spotsup.com/etc/photos/pvc-ducting.jpg

[Jim O'Dell]

One of the pieces is going to have to move. Probably the outlet on the right will have to go up. Only the last picture is showing, so can't tell for sure if it is an outlet or not, but appears to be the exhaust side of a dust collector or cyclone? You might be able to take the piece on the left and pull it out, then put the elbow on the exhaust, and slowly work the other piece into it, but I doubt it. If you can repost with a picture from a little further back, we might be able to tell what you have for sure and possibly make some more/better recommendations. Jim.

edit. After I posted I looked at looked at it again. On the cabinet on the left, how did you seal/glue the PVC pipe into the cabinet? If you used something like silicone or caulk andcan get it loose, put your elbow on then reinstall the PVC from the inside of the cabinet up, and reseal everything. That might work and be easier.

[Burt Alcantara]

Jim,
Here's a different view. You will probably recognize the ClearVue 1400. I'm trying to force a 6" 2729 into the intake. The plenum is on a 2x4 stand and is moveable but only side to side. I'd like to keep it where it is to save as much space as possible.

Burt

[Jamie Buxton]

You could get a short piece of 6" vinyl flexible ducting. You can deform it enough to cram it into that space. That's how some cyclone manufacturers (Griz maybe?) do it.

Another approach is to lose the commercial products. Build a melamine box which will fasten to the top of the filter holder and to the side of the blower enclosure. The pipes both stick into the box. Leave the front of the box off until you get it in place, and then screw it on. The sawdust-filled air will get from one pipe to the other, even if it isn't a nice round 6" diameter cross-section.

[Burt Alcantara]

Jamie,
Some good ideas there. Unfortunately, the horses have already run out of the barn. The filters are very securely fastened to the frame and plenum, with both epoxy and screws.

I've got a collection of various types of fittings, all of which are a major pain and none quite do it. The best of the bunch is a standard 6" PVC coupler which connects the 2729 and flex hose. In this case, there is not room unless I move the filters about 4' away from the cyclone. That takes up too much room for my small shop.

I could go and spend another $40+ and buy a 10' piece of R4 which many people report fits easily over 2729.

This join will end up costing me enough to buy an aircraft carrier.

[Al Killian]

I agree with Jim. Remove the fitting from the box the installl the elbow.Or if possible slide the box down a few inches to slide the elbow in. Using flex hose would be the last option.

[JayStPeter]

How about this. Get 2 6" PVC couplers and saw/grind them so they are just rings that slide over the pieces of PVC pipe sticking out. Put the adj bend you have there on so each end touches the end of each pipe and slide the couplers up and fasten into place with sheet metal screws and Al tape.
In my system, I used some window sealing foam to form a seal between PVC couplers and 6" metal duct. Add tape and it's all good. I specifically used metal adj bends to help with some odd angles and transitioned from PVC to metal and back. Inside diameters are very similar so the transitions are very smooth inside.

[Jim O'Dell]

Is the PVC going into the plenum glued in place like the filters, or did you use caulking or silicone? If the former, ouch, not going to be easy. Is the box glued shut? If so, I'm afraid the only solution is to cut an access hole in the front, cut the PVC pipe out of the top, and cut new pieces to cover the holes. The top one would have a hole for the pipe again, screw it over the existing hole. Insert the pipe into the box where it is flush. Put your elbow, PVC 90, or the metal one you showed in the first picture, on the exhaust of the CV. Then push the 6" pipe up into the elbow from the access hole in the front. Secure elbow on both ends. Secure cover over access hole. The top and side covers could be full size so that the appearance is as it is now, or you could cut something smaller to just cover the opening. That's the only solution I see. Wish it was going to be easier. If the box is not glued shut, it might be easier to open it up rather than cut access an hole. Flex hose would be the other possibility as others have mentioned. It would probably be ok if it was 8", but I'd be afraid that 6" flex would choke down the system a little. I built a new exhaust adaptor and used an 8" metal wye, that split to 2 6" openings, and used 6" flex from there to 2 louvered outlets through the wall. Jim.

[JayStPeter]

Jim,
Here's a different view. You will probably recognize the ClearVue 1400. I'm trying to force a 6" 2729 into the intake. The plenum is on a 2x4 stand and is moveable but only side to side. I'd like to keep it where it is to save as much space as possible.

Burt

I missed this on my last one. If the plenum is movable at all, can't you move it slightly and fit a PVC 90 there?

I might be off base without a bigger view, but looking at that last pic it appears you'd be better off swapping the location of the cyclone and filters so your intake is along the wall. It would keep the ductwork against the wall. I'm assuming, of course, that the exhaust can be rotated around the cyclone. Maybe make the mounts with slots and add shims to line everything up for a PVC 90 if you take it down.

[Roy Clarke]

No big problem, it's only a pipe fitting exercise. You could cut the PVC pipes back until the ends will just mate with the ends of the bend. Then make some wooden flanges to go over the ends of the bend. These can be screwed to the bulkheads that the PVC pipes pass through, and if needed, a couple of packing rings will fill any space between the ends of the bend and the bulkheads.

The simple approach would be to cut the PVC pipes so the ends meet the bend ends, and using the cut off bits, or some a couple of inches long, slit them and slip them over the join and finish with duct tape. Any other straps over the joints will do too. However, it looks like you only have space for the first option.

[Cliff Rohrabacher]

Build a duct angle from wood.

Use the ends of the sheet metal elbow - or any other piece of ducting to create the transition.

[Burt Alcantara]

Didn't realize this was going to be such a hassle. I'm thinking of going back to my original idea of taking the output thru a pants Wye and just dumping each end into the filters. It's easier then I can describe. The problem being I can't find a pants wye locally.

As my filter stack is glued, screwed and shut tight I'm thinking of just cutting the top off the plenum and giving doing something like the above.

It's amazing how much of a hassle ducting is. I guess that's why people spend mucho bucks on metal ducting.

[Roy Clarke]

The advantage with metal ducting is that you can get parts which join together with flanges, and you just have to slip a strap with a toggle clamp over the flanges to seal and hold them together. This means it is possible to remove sections at any time without having to pull them apart lengthwise.

If you make the flange rings as above, then you can fit and remove the bend anytime. This would be useful when you have to renew the filter. You would need enough screws though as this is in the only positive pressure part of the system.

[Jim O'Dell]

Didn't realize this was going to be such a hassle. I'm thinking of going back to my original idea of taking the output thru a pants Wye and just dumping each end into the filters. It's easier then I can describe. The problem being I can't find a pants wye locally.

As my filter stack is glued, screwed and shut tight I'm thinking of just cutting the top off the plenum and giving doing something like the above.

It's amazing how much of a hassle ducting is. I guess that's why people spend mucho bucks on metal ducting.

Whether metal or PVC, it's all in the sequence of assembling things. That's why I used Silicone caulk on my joints. Had to take several apart and redo! Jim.

[Jamie Buxton]

Jamie,
Some good ideas there. Unfortunately, the horses have already run out of the barn. The filters are very securely fastened to the frame and plenum, with both epoxy and screws.



Burt --
Reread my first post. Neither of my suggestions requires moving the plenum or the frame. And they'd both be pretty easy to do.

[Burt Alcantara]

Jamie,
I reread your post and you're right! I'll try both ideas and see what happens. I think either way I will get one to work right.

Thanks,
Burt

[Jim Becker]

Since this is on the outlet side of the unit, I'd simply use a short piece of quality flex hose and be done with it. Any form of hard duct, metal or plastic, is going to require you to move something to install it...either the plenum or the cyclone.

[Burt Alcantara]

I found that I could tilt the plenum back enough to get the metal elbow in place. There a some fairly large gaps between the elbow fittings and both sides of the 2729 but at least it's in.

What is required to fasten this? Should I glue it, screw it, both, neither? I have ducting tape and caulking and I will tape this up like a mummy.

ClearVue owners: the clearance between the cyclone and the floor is 17". I can buy a metal can to fit but it is pretty small. Would it be possible to attach a 45 gallon lawn and garden bag and hold it down with cinder blocks?

Thanks,
Burt

[Jim Becker]

Burt, calk should do the job for that particular fitting...it's not going to fall off no matter what, so sealing is more important than any kind of physical strength.

[Burt Alcantara]

Jim,
That's good to hear. Once sealed up I only have to wire the mag switch. Of course there is the main ducting...arg....:(

[Jim O'Dell]

Jim,
That's good to hear. Once sealed up I only have to wire the mag switch. Of course there is the main ducting...arg....:(

Different Jim here, but you're just getting started! :eek: :D :D Work from the cyclone and away, that way you won't run into any more problems of a fitting not wanting to go in. I'm guessing you are using PVC for your ducting?? Be sure to get you a tube of pure silicone to seal the joints after you dry fit everything. Be sure to keep us posted on your progress! Jim.

[Burt Alcantara]

Since I put a lathe in the shop, with a grinder, everything got moved around. I'm going to leave things as they are and see if I can take advantage of all of the Wynn flex hose that's taking all the space in the shop.