Expanding foam

[MyHigh]

So, I've been researching materials for a sound/temp barrier for the runner.
I got to thinking about expanding foam, that could be used in the rear of the runner behind the interior panels. Seeing how trapped air is basically the best form of insulating I'm half tempted to give it a try.

Problem:

If it doesn't work, or even causes problems I will have a hell of a time trying to remove the material. So, I'm wondering if anyone has experience in this particular application, or any insight as to problems that this might cause. One thing I'm worried about is water and how it might be problematic if it can travel between the foam and the inside of the body panels. If it works I can even see using it in selected section of the doors to hopefully add a more solid sound when closing them.

 

[Rcastle]

I personally would not... It gets everywhere, is near impossible to remove and I remember seeing a picture of someone who did it to an older car and did not allow for expansion and blew all his door skins off.

Doing a quick Google search people have done it so... I might spray it into a plastic bag inside the panels so that if you ever need to remove it, it will still be a pain in the ass but not glued to everything.

 

[96LTDrus]

Bad idea IMO, it will only serve as a trap for moisture, which in turn may cause severe rust issues down the road.

 

[wc11]

The only possible benefit you could possibly attain is that your truck might float.

Dynamat or anything like that is the only way to go.

 

[AZBub]

The more posts saying "bad idea" the better. Don't do it. Stick with what is known to work.

 

[gamefreakgc]

I've used that foam around the house (great for sealing gaps where cold/hot air gets in) and have used it to plug up some holes in my old pickup. But that thing was a little bit of a beater so I didn't really mind what happened to it.

One can would only fill about one door, so that'd get more expensive than you think real quick. Plus it does not come off, it's extremely sticky and messy.

If you are looking for a sound/insulating barrier, look at the PS Ensolite from RAAMmat, it's fairly inexpensive for what you get. 2-3 yards would be enould to line each door panel instead of the flimsy plastic barrier. I just finished putting that and the sound deadening material (only useful if you are upgrading your speakers) and it is getting quieter. Most of the noise coming in is from the rear cargo area though, just a heads up.

Ensolite IUO Peel and Stick --- 1 yard (13.875 sq ft) - RAAMaudio Inc.

P.S. don't put Ensolite on the outer door skin or you'll muffle your speakers too much

 

[MyHigh]

Lol, had a moment of Clarkson and crossing the English Channel.

Thanks for all the input, I defiantly do not want to blow out the panels on my rig
:lmao:

 

[MStudt]

I've used stuff called Boom Mat before, and it works decently. It's a spray on, but not a foam.

 

[thor999]

Yeah don't do that.

 

[Rhoov1]

I recently had to replace some rear subwoofers mounted in the side panels of an older jeep (like 70's model) and they used the expandable foam to seal up the area and make it more of an enclosure and sound deadening. Absolute nightmare trying to remove that crap. Dynamite, Accumat, Hush mat, Stinger Road Kill. Stick with the real deal. They make all kinds of different types for different applications. After selling sound deadening for over 20 years in the car audio world I have seen it all used and the mats work the best! The idea behind the sound deadening mats is to add weight to the metal and essentially change the frequency at which they vibrate. Adding expandable foam adds little weight with little benefit and a whole mess to deal with.

 

[neokhz]

If you do it, put plastic or put it in a trash bag. Don't spray directly to car. Will cause rust.

 

[BrianSD_42]

I used that exact same foam to fill in a gap in my wheel wheel that resulted after some rigorous trimming. It expands out quite a bit but it was fine since After it dried I cut it with an exacto knife and then painted it black.

What you are describing though ... Dont do it.

Use sound deadening mat or sound deadening spray instead. That foam may cause squeeks among other problems.

 

[jstim]

Lol, had a moment of Clarkson and crossing the English Channel.

Thanks for all the input, I defiantly do not want to blow out the panels on my rig
:lmao:

We're gonna cross the English Channel faster than beardy Branson!!!:rofl:

 

[Nervo19]

If you do it, put plastic or put it in a trash bag. Don't spray directly to car. Will cause rust.

That's a good idea to put it in a plastic bag so you can remove the whole thing in the future.

I've seen on some boating site where someone experimented and Great Stuff will absorb water over a period of time. So water logged foam next to a steel panel...not good.

 

[Kryptoroxx]

Take a look at secondskinaudio.com. Every now and then they have a sale on b stock stuff. Still better than dynamat any day. I got 90 sq ft for about 230 with shipping. I did the entire 4runner and I still have some sitting in a box.

I also did all the doors and the tailgate. Made a big difference in road noise and environmental. For reducing tire noise you can also attack it from the outside by using a rubberized undercoating.

Hope this helps man. I would NOT use spray foam. You will regret it.

 

[Doc2012]

You can use "Peal N, Seal" from Lowes as well.

It's about 17 bucks for a 33 foot roll. I used two and a half rolls to do the entire passenger compartment, not the doors yet though.

It's the same thickness as Dynamat, 50 mils., and is BASICALLY the same stuff. Only difference being that it's an asphalt base instead of a butyl base.

I did it during the day and night, and one "trick" I found was to use heat on it, like a propane torch or a heat gun, to make it REALLY tacky.

This stuff sticks straight out, but using the heat makes it "flow" a little more.

I'm in NC, and it's been close to 100+ all summer, and, even though I DON'T drive my truck right now(working on stuff now that I have another DD), I can't smell it at all when I open the doors.

Clean floor pan, (I used Mr. Clean spray stuff) and go with it. Cuts fairly easily with a razor blade.

You can find it in different widths, though I feel the 6" is perfect to work with.

http://www.amazon.com/MFM-Building-Products-50036-Peel/dp/B0004I0MG0

Shop Peel & Seal Instant Waterproof Repairs 6-in x 25-ft Aluminum Roll Flashing for Chimneys, Roofs, Doors, Vents, Gutters, and Egress Windows at Lowes.com

I plan on getting some aluminum tape to go over the seams as well.

 

[cp99sr5]

Beyond what everyone else mentioned, I tried to use it in a tube, I do astronomy so I want to eliminate vibration in an aluminum tube that is part of a mount for the telescope. What I found is that the foam needs air to fully dry. When I filled the tube, I had thoughts of it expanding past the ends so then once dry, I would just shape it and have a solid foam core. What happened is that it never really dried on the inside and remained in a liquid form so when I punctured the ends trying to shape it, crap started running out. I finally ended up trying to remove it, what a freaking mess! Anyway if you choose to use it, layer it in the cavity, wait for it to fully dry and continue to layer until full. Like mentioned, it absorbs water, getting heavier over time and will promote rust.

A lot of people recommend using Peal n Seal which is a rubberized asphalt flashing tape for sound deadening, I used Select Window and Door Flashing which is a readily available butyl rubber flashing, it works and you don't have the smell issues when its hot with the asphalt based flashing. Some people have smell issues and others don't so its a preference thing. Peal n Seal is about $5.000 cheaper also.

Good luck!