# dust collection, metal duct, question



## nuckleheadbob (Dec 2, 2014)

Recently installed a new dust collector that required a duct upgrade. After much humming and hawing I decided to use metal duct from the Depot. I know, I know, some warn that it will collapse when the thing is turned on but my son-in- law has been using it for years with a real beast of a machine with no problems. 
When laying it out I noticed the wyes are all crimped on the wrong end for air coming in rather than blowing out. The question is; will this backward joint cause a significant loss of flow or I am being too anal?


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## Redoak49 (Dec 15, 2012)

Yes, it will cause a loss as it adds significantly to the friction and disrupts the air flow. Also, you will have a buildup on the rough edges.


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## nuckleheadbob (Dec 2, 2014)

Redoak49,I guess that'd the downside of hvac pipe. What I have been doing is hard crimping sections of 6in pipe to fit inside the crimped wye fittings. This makes for a real ugly joint and its hard going working alone. There must be a better way.


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## JBrow (Nov 18, 2015)

Nuckleheadbob,

I agree completely with Redoak49.

I have used that crimping tool and like you, I hate it from beginning to end. One alternative option would be to employ a butt joint when connecting the pipes, supporting the butt joint with a draw band connector. It may be beneficial to seal the butt joint with some foil tape before putting the draw band connector in place. It may be difficult to seal against air leaks after the clamp is in place. Here is how these clamps look…

https://www.google.com/search?q=draw+band+connector&tbm=isch&tbo=u&source=univ&sa=X&ved=0ahUKEwjP97LbueDSAhUL5IMKHRk7AkYQsAQIIw&biw=1366&bih=620

If you scroll down to Overlap butt joints with draw band connectors, you can see how the draw band connector is installed…

https://www.familyhandyman.com/heating-cooling/round-ductwork-installation-tips/view-all

I would think that if finding draw band connectors locally is a challenge, it could be easily made by cutting your own from some sheet metal. At least a 1-1/2" overlap of the band over each pipe and of the end of the band would be needed for a good air seal. Although not ideal, some short zip screws could hold things together.


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## wapakfred (Jul 29, 2011)

You could get some of the foil duct tape and cover the joints on the inside (at least some of them) to smooth things out. You might even be able to hammer out the existing crimp and put a new one on the correct end…but it probably wouldn't be easy.


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## nuckleheadbob (Dec 2, 2014)

JBrow, Thanks, Ive never heard of drawband connectors. We have a metal shop in town that may have them. Looks better than what I'm doing. Now to work out the blast gates.


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## Hermit (Oct 9, 2014)

I bought a tub of the ductwork sealant and used a paint stick to apply it inside on all those joints. Give it overnight to fully dry so you don't have a mess. I then also applied it on the outside as needed along with foil tape.


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## Redoak49 (Dec 15, 2012)

This is one of the reasons I went with drain pipe. Can you find a place which sells uncrimped pipe.


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## nuckleheadbob (Dec 2, 2014)

Yea, having second….. and third thoughts on the metal pipe. In deep now so moving forward. If it doesn't work right I'll have to tear it out. If I can figure out how to post pictures I'll do that.


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## Finn (May 26, 2010)

You can just cut off the crimps and the beads on the wyes. Takes tin snips and one minute.


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## pintodeluxe (Sep 12, 2010)

Hmm, I special ordered 26 gauge pipe and wyes from home depot, and everything fit fine. I did orient the joints for best flow in a vacuum system. If you had some that were crimped on the wrong end, I doubt it would affect performance much as long as you foil tape them.


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## English (May 10, 2014)

When I did my DC I used Home Depot Flue Wyes You have to order them, but they will ship them to your home for free. They have the crimps on the correct end.

http://www.homedepot.com/p/Master-Flow-6-in-x-6-in-x-6-in-26-Gauge-Flue-Wye-26FY6X6X6/202258555

I got my duct from Ferguson Plumbing Supply. There 26 gauge duct was cheaper than the 30 gauge that Home Depot sells.


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## nuckleheadbob (Dec 2, 2014)

Dang it English! If I had just held off. Do they have flue elbows also? We have 4 Ferguson stores near by. Dang it! Thanks


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## English (May 10, 2014)

The Elbows can be installed for either positive or negative flow, just turn it around. If you have the crimps on the inlet side of the fittings saw dust will collect on the crimps and may cause blockages.


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## nuckleheadbob (Dec 2, 2014)

No problems with the elbows, it's just that they are so thin. Popped a couple apart moving the pipe around. Ordered flue wyes yesterday, thanks for the info.


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## Bumpy (Jan 30, 2017)

You can straighten the crimped end using pliers, also purchase a crimping tool, about 20.00. I have almost 100' of 6" duct (thin wall) installed. No issues with collapsing duct or connections.


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## nuckleheadbob (Dec 2, 2014)

Ok! Good news…..sorta. Ferguson is the way to go for metal duct. (Thanks English). And Home Depot for flue wyes that work great. So now hooking up 6in flex hose to metal is the problem. I want to run 6in to most of the drops but its real tight going on. Onedia makes a fitting that allows easy assembly and disassembly but if there is something else that's works I'd love to hear it.


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