making a silicone seal

Belgian1979vette

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Want to make a silicone seal that will glue to one side of my airbox but not to the lid. Tried using vaseline on the lid, but for some reason the rtv won't harden.

Any other ways to do this ?
 
Masking tape on the open contact edge?? let it all cure up, ??? then open/remove tape, check for seal with a piece of paper ?? how about water pipe insulation foam?? foam rubber from some cushion or old car seat?? cut strips/RTV glue in place...BOX?? what box?? free form thinking now.....

:surrender::smash:
 
Want to make a silicone seal that will glue to one side of my airbox but not to the lid. Tried using vaseline on the lid, but for some reason the rtv won't harden.

Any other ways to do this ?

Silicon may not cure entirely due to the lack of moisture.
If you mix type I silicon with corn starch, you're adding just enough moisture to make it fully cure.
That's what Sugru paste is made of.
 
Silicone will not adhere to wax (like a candle, not car wax). And wax will not interfere with curing.
 
Masking tape on the open contact edge?? let it all cure up, ??? then open/remove tape, check for seal with a piece of paper ?? how about water pipe insulation foam?? foam rubber from some cushion or old car seat?? cut strips/RTV glue in place...BOX?? what box?? free form thinking now.....

:surrender::smash:

Some types of foam do not stand heat all to well.
 
Want to make a silicone seal that will glue to one side of my airbox but not to the lid. Tried using vaseline on the lid, but for some reason the rtv won't harden.

Any other ways to do this ?

Silicon may not cure entirely due to the lack of moisture.
If you mix type I silicon with corn starch, you're adding just enough moisture to make it fully cure.
That's what Sugru paste is made of.

Yes the moisture probably is the issue here. I'm currently doing some small tests with dish wash soap and vaseline in a solution of white spirit but the curing is really slow.

Cornstarch ? Never heard of that one.
 
Try taping wax paper to the bottom side of the hood. Test on the work bench first of course, but that may do the trick.
 
Not sure how available something like this is in your area, but this is one thing you can use:

http://www.smooth-on.com/Release-Agents-and/c9_1123_1226/index.html

Also, a cheap (at least here, at the "dollar" store) substitute for this is hair spray. You need to test it first to determine how many coats you need to get it to release consistently. You can mask off the area around where you're spraying to limit overspray.

Mike
 
Hairspray ?
Ok will test that.

So far nothing really worked except dish wash detergent. But it also seems to release easier from the side it needs to stick to.
 
Ever heard of "Pam" cooking spray? I use that stuff a lot as a release agent for fiberglass work.... Works great !!!!

For silicone/RTV - for what you are doing - I'd try applying the RTV to the lower part of the airbox, let it partially cure.... Then brush a "non stick" agent to the mating surface on the lid.... Pam, olive oil or wax.... Then when the RTV is partially cured set the lid on it so that it forces the RTV into the shape you want (flat).....
 
Ended up using the type of seal that is used to get windows/doors draft free. It's a foam type seal. I found info on the inet saying it was temperature proof till 120°C.

Did some tests with a piece of alu in the oven during 20 minutes at 100°C and it was ok.
 
But will it hold up to the types of chemicals circulating in an engine compartment? That was the downfall I found a couple times using "household" materials under the hood.

One I found that does hold up is a foam chinking for use between logs of log homes. It's a fairly dense foam rubber seal strip that comes in rolls. I copped several rolls left over from a job we did years ago, one is about 1" wide x 5/8" thick, the other 1/2" wide x 3/8" thick, with sticky on one side. I have used it in numerous places on both my old truck and my car and it hasn't degraded from sunlight, temperatures or fumes/chemicals.

And that just jogged my memory: I remember many years ago using soft thick walled vacuum tubing for making seals just like what you need. About 1/8" interior diameter size, but close to 3/8" OD, it was softer than oil or fuel lines, for use on engines. I slit it and glued it on the metal edge with silicone sealer and clamped a lid down on it.

And looking at your photos again, as it appears to me, wouldn't just flat 1/8" or so thick rubber gasket material glued (or even riveted) to the flange of your box work to seal the lid?
 
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Couple of good ideas.

The sealing of the lid is not the only thing I'm dealing with. I also have to seal the box against the stacks, which is an even more difficult area.

I hope the foam seal will hold up to it.

Normally I would expect that airbox to stay fairly dry. There is no pcv connected to it.

The only thing I need to worry about in there is fuel. So I just put a piece of that strip in gasoline. After 10 minutes it was still there. Will leave it in there the entire night and see how it is tomorrow.
 
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