Sealing DC adj metal elbows?

[Bruce Darrow]

Hi guys,

For those of you who have used the adjustable metal elbows, how did/do you seal the joints?

I've done it with silicon - hate the process.

I'm currently sealing the connection joints with foil tape - much easier than silicon. I'm hoping that it will hold up better than duct tape. It is definitely less tear resistant.......got to make sure there's no flexing when handling and installing pre-assembled sections, even riveted.

So how about those articulated joints? I have my doubts about using the foil tape there.

Thanks,

Bruce

[David Kumm]

There are many types of tape. I like the heavy tape with the removable backing for the joints and the thin foil with no backing for the elbows. It folds easier. Hardware stores and HD usually have several options. I use tub and tile caulk around the blast gates as tape doesn't work well there. Dave

[Cyrus Brewster 7]

Rubber spicing tape works excellent. When stretched it amalgamates to itself and will also fill crevices. There is no leaking. Just makes sure you overlapped it by about 50%. You can get this at HD.

When I use it I will cover it with regular duct tape just to protect the rubber tape underneath.

The X-Treme tape advertised by woodworking stores is basically the same stuff - just wider.

[John Lanciani]

Gray latex painters caulk. Cut the nozzle as small as possible, gun the caulk into the seams and wipe lightly with a damp rag. Clean, cheap, nearly invisible, and easy enough to remove if you need to change the angle. If you really want to get the caulk into the seams, run the DC with all of your gates closed while youre caulking and it will get sucked into the larger gaps.

[Alan Bienlein]

Metal foil tape used for HVAC.

[Ole Anderson]

I used clear silicone in a caulking gun with a small tip hole and I thought it went quite easily, and you can't see it when you are done, looks very clean. A squeeze tube might be more difficult though. It is a bit more difficult to get behind the joint though, although tape can be difficult there too. A dab of silicone on your finger wiped in the joint there works. The system is so much quieter without all of that sucking noise in the joints when you get done and the efficiency goes up.

[Jim Finn]

I am a retired sheet metal worker and have sealed more pipe elbows than I care to remember. We used silicone caulk on all joints but I am sure that any caulk would work.

[Kent A Bathurst]

Mine are sealed with the foil tape. Looks the same as it did when I installed it 4 - 5 years ago.

[Bruce Darrow]

Thanks for the replies.

I'm assuming it is rubber splicing tape, not spicing......I've eaten some things that seemed to spiced with same......I'll look into it.

I'm going to try one with the foil tape and see how it goes. If I don't like it, I'll try something else. I always make a mess w/ silicon, but I'll go back to that if I have to. Or the latex caulk. Water solubility is nice.

[Ron Natalie]

They make a duct sealant (you can buy it in the borgs) that you paint on.

[Jim Finn]

The tape or the paint on stuff also work well but the clear caulk on the seams looks better.

[David Kumm]

The tape or the paint on stuff also work well but the clear caulk on the seams looks better.

The foil tape companies do seem to strive for the ugliest look possible. Sort of fits in my shop though. Dave

[Bruce Darrow]

I beg to differ, David. The aged duct tape look beats all others, hands down. Thin silver ribbons hanging down with dusty webbing kinda floating around and then there's the glue residue.......

[Jim Becker]

I have used both caulk and the foil tape. What I haven't tried is "real" duct calk which I suspect will work better than either of the other two. In general, however, all of my duct work joints are sealed with foil tape. It works great as long as there isn't any movement. You do need to make narrow strips to do the elbows effectively, however...

[Bruce Darrow]

Jim,

Great steer on using narrow strips. A straight edge and a sharp utility knife makes cutting 2" tape into 1" tape a breeze, and 1" strips make a much neater seal.

Funny how such simple solutions can elude one.

Coming to the end of the project - this is my shop at work. I am applying all I learned when tin knocking my own shop to get a 3 hp Sternvent working the way it should for the first time in over 15 yrs, in 3 different locations.

The crowning achievement (I hope!) will be a Long Ranger with blast gate switches - this should make it nearly impossible for the so called "carpenters" who come through all too frequently to leave gates open, or not open them to begin with.......we shall see.

Thanks again!

Bruce