expanding foam

[aussie75series]

I saw on a tv show the use of expanding foam in vehicle sills and pillars to strenghten the body.I'm doing up a EK Holden (57 Chev) and thought if I filled the sills not only for rigidity but would it stop rust be filling every space thus excluding air therefore no rust ,well thats my theory what do you think.

 

[Japan4X4]

I think when you go in to repair the rust in a few years you will curse the foam.

But that is just my opinion.

 

[bandy rooster]

i think if you had a perfect and i mean perfect seal in between the foam and the elements it would work.. although i've only ever seen the foam or expandable foam used in plastic bumpers and other plastic parts to increase there rigidity...but then again i haven't seen alot of things

 

[Mace]

that foam typically does more to INCREASE rust issues..

57 chevy should not need reinforcement..

 

[toddslater]

X2 on what Mace said.

 

[brownbear]

foam likes to trap moisture. So it WILL cause rust.

 

[AATLAS1X]

The new F series trucks have all the pillers filled with expansion foam.

my .02

 

[webelk6]

expanding foam is used to fill mistakes in shotty carpentry. I found foam in a fender I bought when restoring my old fj62. Foam=Crap.

 

[Landcruisin'60]

Find lunyou's rebuild thread. That will convince anyone that foam=rust!

Here https://forum.ih8mud.com/showthread.php?t=150109

 

[Fantom]

A friend of mine bought a truck where the very intelligent PO used the foam inside the chassis under the misguided hopes that it will not rust. When my friend got the truck he did the frame off on it, after many days of swearing, bleeding, and removing the crap he discovered the full effect. The foam worked great to trap moisture and not release it. The entire frame was garbage. I have seen it used in body panels, the best case effect I saw was that after your panel rots off you have a perfect shape of it in the foam so you can just pain that and no one will notice. The other benefit of foam is that when you go off roading and damage your new "panels" you can just spray more of it on and shape it with an x-acto knife. Let's not forget the fact that since you will have no sheet metal your fuel economy will improve due to lower weight.
P.S. - yes I am a sarcastic SOB.

 

[aussie75series]

Well thats that theory shot in the bum.No foam.Thanks everyone

 

[Tofudebeest]

I put foam in my windshield frame just to provide backing to keep the aluminum tape in place until I could weld in new sheet metal or replace the roof (I'm doing the latter). In the couiple of months it has been in place, the rust blossomed like weed grown in miracle grow. It ABSOLUTELY traps moisture in. Moisture is the food that rust craves.

 

[GarnerFJ40]

Just got done removing the foam the PO put in, and all the rust.... SOB...

 

[lunyou]

if you want to know what expandable foam does to body parts check out my chop top link in my sig line........IH8FOAM

lunyou