Great Stuff expanding foam?

[bikin' Ed]

Originally Posted by saunders1313

You mean like the silicone you can get for sealing bath tubs? What would be the best stuff to get? I'm not looking to build on this, I just want to seal up all the gaps in the front, but be able to paint it so I looks half decent.

Almost like that. There is one made for sealing around glass block windows that I use. (I've used different brands they've all worked.) I'm guessing the outdoor stuff is formulated a little differently for temp extremes, UV exposure etc.

[extragoode]

I've thought a couple times about using it as an injection mold in a plastic bag. Arrange plastic bag in hole you want filled, like a fog light hole, hold pressure on it until is stopped expanding, paint. A little trial and error with the amount injected would be necessary, but you would end up with a removable, perfectly shaped block if it worked like I think it should. I probably won't work that well, though.

[bikin' Ed]

Originally Posted by extragoode

I've thought a couple times about using it as an injection mold in a plastic bag. Arrange plastic bag in hole you want filled, like a fog light hole, hold pressure on it until is stopped expanding, paint. A little trial and error with the amount injected would be necessary, but you would end up with a removable, perfectly shaped block if it worked like I think it should. I probably won't work that well, though.

I think that would work great! A lot of recumbant home builders have put foam in a plastic garbage bag to form "custom" seat mold.

[TomO]

^^^ that's an idea definitely worth trying out. I'm going to have to try that as well.

[whokilledthejams]

Originally Posted by extragoode

I've thought a couple times about using it as an injection mold in a plastic bag. Arrange plastic bag in hole you want filled, like a fog light hole, hold pressure on it until is stopped expanding, paint. A little trial and error with the amount injected would be necessary, but you would end up with a removable, perfectly shaped block if it worked like I think it should. I probably won't work that well, though.

I had an idea similar to this, except using aluminum foil to make a form. However, I could see a plastic bag working.

The biggest problem I would have is in trying to make a flush-fitting block for my lower grille. I've been brainstorming today, and I think I might cover the grille opening with foil (since it would keep its shape better than plastic), then covering the opening with foil or plastic covered cardboard (or some other semi-rigid material), and injection-molding that way. Then, I could take out the resulting piece, shape it, paint-prep it, attach it to the lowest part of my bumper (which is a separate piece of fiberglass), then smooth it all over with some bondo and paint.

In my head, this is an awesome plan, though it would probably be a huge headache. The upside is, despite the minimal aero gain vs. the coroplast block, it would hypothetically look nice.

[Sayyad]

Try foam insulation tape, I think it is usually used as weatherstripping for windows and doors. I don't know how long it can handle UV for but it's easy to apply and equally easy to replace, and is available in a variety of densities and colors, as long as you want white, gray or black.

[COMP]

Originally Posted by whokilledthejams

Great Stuff used to make a black expanding foam for landscaping (like garden ponds and such-- my dad has used it in his), but it appears they don't anymore. Reading the Great Stuff site, however, they do specifically recommend painting the foam in applications exposed to sunlight.

I have, however, found this:
Pur Black NF Expanding Foam - Foam Products - Pond Accessories

It seems kind of pricey, but is meant to be used outdoors, and will allegedly withstand heat, cold, moisture, and light.

haven't seen that

[Big Dave]

Great Stuff is exactly the same as Gorilla Glue but has hexane in it to loft up the foam. Some carpenters now use it in place of nails to attach windows to the house frame.

Silicone is difficult to paint. Latex caulk is paintable.