Expanding Foam

[RogerC62]

As far as absorbing water goes, I would think the stuff at the home improvement stores does not. I can't imagine you could use it on your house if it did. You'd get a lot of wood rot! I have some and I used it to seal and insulate any gaps when I installed my windows last year. I'm also using it to seal gaps in my house eaves before I paint.

I think if there is any moisture or condensation present when sprayed in a car, it would trap it and the metal would eventually rust out. The foamseal stuff may have rust inhibitors in it.

 

[Platonic Solid]

Just be careful and do some testing on something that isn't important to you before going nuts with expanding foams. I've tested the household insulating stuff in a small (approx. 6" cube) spot welded box with one hole in it and it significantly deformed the box when it expanded. This was a very unscientific test and my goal was to see if it was strong enough to deform thin gage metal (20 Ga. - 0.036) and it was.

 

[txwoody]

As far as foams you would be looking for a pillar foam there are several companys that make them 3M 8458, duramix 4330. SEM makes one and as someone already said Fusor makes one. These are made to OEM spects so I would think they would be a little better than the foam in a can.

 

[68RCodeConv]

I tried using the Home Depot expanding foam as insulation in my walls. Pumped a bunch if it through a hole in the sheetrock.

When it expanded it blew out a section of the sheetrock. This stuff is powerful when it expands.

 

[chromedog]

i guess it should be pointed out, comparing the stuff from lowes, and automotive foam is like comparing apples and oranges... they are both fruits, but the similarities end there. great stuff is an aerobic foam,that is, when air hits it, look out! the foam used for stiffening windshield posts is a 2 part product that uses a special applicator gun. also, great stuff sets up, for the most part, as a dry crumbly mass... the foam we are talking about has the consistancy of a rubber ball when it sets AND the expansion factor for most of them is 1:10. i guess what im saying, in a nutshell, if you want to experiment, have at it. just understand you wont get the same results from greatstuff as you will from an automotive foam.btw, ive pumped the handlebars of a motorcycle full of fusor foam... no more tingling in the hands!

 

[Nemesis67]

i guess it should be pointed out, comparing the stuff from lowes, and automotive foam is like comparing apples and oranges... they are both fruits, but the similarities end there. great stuff is an aerobic foam,that is, when air hits it, look out! the foam used for stiffening windshield posts is a 2 part product that uses a special applicator gun. also, great stuff sets up, for the most part, as a dry crumbly mass... the foam we are talking about has the consistancy of a rubber ball when it sets AND the expansion factor for most of them is 1:10. i guess what im saying, in a nutshell, if you want to experiment, have at it. just understand you wont get the same results from greatstuff as you will from an automotive foam.btw, ive pumped the handlebars of a motorcycle full of fusor foam... no more tingling in the hands!

Amen brother.
That's one of the reasons I started this post. I wanted to let everyone know that stuff like this exists and the benefits from it. Sound deadening, moisture resistance, lessening vibration, chassis stiffening. All pluses in my book.

 

[BlackGMC]

I was thinking about this foam stuff last night, and I think it would work great in the rear frame rails on a mustang. Since the rear rails are not as thick as the front rails, this foam idea could really help stiffen up that area. HMMMMMM, I might have to really think about this when i start working on my rear section....

 

[BlwnGazkit]

You can also purchase the foam from www.shopmaninc.com

It's the same foam used in boat hulls.

 

[RUSTYNUT]

The home stores sell foam for use around doors and windows that are much less damaging. If you use this in rocker make sure you drill some releif holes to allow a place for the extra to vent out and 100 % sure are completly filled. This stuff sticks to every thing so mask everythig very well. I've been thinking the same thing, but have always wondered about condensation etc.

 

[Nemesis67]

The home stores sell foam for use around doors and windows that are much less damaging. If you use this in rocker make sure you drill some releif holes to allow a place for the extra to vent out and 100 % sure are completly filled. This stuff sticks to every thing so mask everythig very well. I've been thinking the same thing, but have always wondered about condensation etc.

You don't want to use the home store stuff. I thought about using it too. But after a little research and some good advice from some of our StangNet brothers, I've reconsidered using it. Go for the stuff that was designed to put into car frames. The home store stuff will not always set up and cure like it's supposed to, which will cause problems in itself. Plus it does nothing to strengthen ( increase rigidity) the framerails I plan on using the stuff Infinity uses in their Q45 cars. It's called Foamseal, Google it and you'll find out it or another similar product is the way to go.

 

[ericl]

DO NOT use any of the stuff for home insulation in your cars. The kid that owned my mom's cuda did this in place of seam sealer. EVERY surface that this foam was on was rusted. Not thru the panels but it was rusty. This is an open cell foam that traps and retains moisture. I'm sure that there are some foams that could be used for this purpose but not the stuff from the hardware store.

 

[latamud]

DO NOT use any of the stuff for home insulation in your cars. The kid that owned my mom's cuda did this in place of seam sealer. EVERY surface that this foam was on was rusted. Not thru the panels but it was rusty. This is an open cell foam that traps and retains moisture. I'm sure that there are some foams that could be used for this purpose but not the stuff from the hardware store.

Agreed! I admit I used the home stuff on a car I restored a long time ago. It was great because it built up areas that didn't have anything for Bondo to catch on BUT...in the end I was getting a lot of rust bubbles through the paint in those areas. I ended up going back in a couple years later and removing all the foam. Painful.