Spray foam inside cab roof?

[tonypaul]

Im thinking about spraying "spray foam" inside the roof panels to cut down on noise. I was thinking of using some long tube to slip over the nozzel to get up in there preety good. I would go through the sunvisor holes, and the cab light hole. I have used this stuff before around the house and Im affraid that it might push out areas of the roof. Im Dynomatting everywhere inside the cab and doors, Im really trying to get it quite as possible inside the cab.
Would this be a bad idea?

[DaSchlange]

I cannot see why it would be... I mean, if you're gonna do it in the doors or something that would put the foam in the way of mechanical parts moving it would be a problem, but simply putting it in an empty space in between panels wouldn't cause any harm. That stuff won't push out metal though. The only other thing I could think of is if there is an acid in that stuff that would cause the metal to corrode over time. But I doubt that as well. I would do it myself, not a bad idea. Plus you'll have better insulation for cooling or heating...

[gearys 5600]

I would like to hear if anyone has done this also.

[red69ss]

they make different grades of it and some expand more than others ,as long as you use minimal expanding it would likely work. I would research whats in it as already mentioned and its affect on metal.

[mbgmike]

Originally Posted by tonypaul

Im thinking about spraying "spray foam" inside the roof panels to cut down on noise. I was thinking of using some long tube to slip over the nozzel to get up in there preety good. I would go through the sunvisor holes, and the cab light hole. I have used this stuff before around the house and Im affraid that it might push out areas of the roof. Im Dynomatting everywhere inside the cab and doors, Im really trying to get it quite as possible inside the cab.
Would this be a bad idea?

Most all new cars and trucks have foam sprayed in them for noise control. You will have to get the correct stuff. The kind that does not attract moisture. If you have rust in there now don't know if its a good idea. All the new cars have corrosion protection far superior then back then.

[too much stuff]

I will say it will hold moisture and give you problems down the road. If you are worried about noise, maybe something with a custom headliner...

[72lb4x4]

I would think that if used on a vehicl, closed cell foam would be the way to go. My understanding is open cell foam can act like a sponge and hold moisture--bad.

I've never tried it so don't trust my opinion. Spend some time researching the subject.

[cdowns]

for noise problems i always just got bigger speakers

[Willys47]

I have seen it done and it worped the inner roof section and short of cutting the inner roof out there would be no way to fix it.

[68shortstep]

Originally Posted by 72lb4x4

I would think that if used on a vehicl, closed cell foam would be the way to go. My understanding is open cell foam can act like a sponge and hold moisture--bad.....

Sorry in advance for the long post.

I'm, not a plastics chemist, but:

1. Most of the generally yellow or tan-colored expando foams tend to be approved / recommended for use in sealing cracks around windows, doors, foundation, etc, to tighten-up energy efficiency in houses, where they would get some amount of exposure to moisture from both inside & outside the house sources, so I doubt the foams would be recommended for that use if they would absorb & hold moisture, if for no other reason than that would promote wood rot & mold growth.

2. The high $$$ bass-boat manufacturors here (Ranger, BassCat, Viper, Cobra, etc), all use expando foam to fill the voids in their boats for added floatation --- Most of those boats won't sink, even if they're swamped level full of water, & have a 200 HP motor bolted to the transom. Those voids in the boats do get exposed to water at times, so I doubt those foams would be used if they absorbed water.

3. The Corps of Engineers here on boat dock floatation is making everybody change over from the old white "coffee cup" style bead-foam which DOES absorb water & gets waterlogged & breaks down in water eventually, & they're making everybody change over to the newer expando foam on boat docks.

4. Why not just test it out ??? Take a clean & rust-free piece of steel & spray a big blob of the foam you might want to use onto it, let it set up & dry, & put it outside & spray water onto it daily for a month or so. If the neighborhood dog comes by & helps, so much the better. When you think it's been long enough, scrape the foam off the steel & see if absorbed water or a chemical in the foam has started corroding the steel where the foam was. My guess is that the foam area will be rust-free & everywhere else on the steel will be rusted, but that's just a guess.

PS: I'd use it, & not worry about it.

[Hottrucks]

Originally Posted by 72lb4x4

I would think that if used on a vehicl, closed cell foam would be the way to go. My understanding is open cell foam can act like a sponge and hold moisture--bad.

I've never tried it so don't trust my opinion. Spend some time researching the subject.

Check the boat forums the foam used in boats is closed cell..that being said I have dug ALOT of foam out of boat that where water logged...that also being said your roof had better not be under water all the time or you have other issues

[Shaky]

Here's what it looks like in there in case you're curious.

[Richard H.]

Well if it helps any for confidence ,I am shooting mine with body wax first and still looking for the foam ford uses to fill with. If nothing comes up I will use Great stuff.

[Beuford]

X2 with Red69. I would use minimal expanding foam because it may hump up your roof and there is no way of getting it out short of cutting the roof. I put a good headliner in my truck and it's quiet enough.

[tonypaul]

All very good points..... I just painted my cab on saturday, came out pretty good. My cab roof is black and being here in Texas (always hot) I doubt moisture would ever have time to develope inside the roof. Im mostly worried about expansion. I think I will do some research into various spray foams and give it a shot. I only wish I would have done this before paint most of those spray foams are really messy....

[ChevLoRay]

All those questions and all those comments still don't answer your question, do they? All points were valid and thought-provoking. As the owner of a truck that suffered because of the wrong RTV material, the idea that the foam might absorb moisture or react with the metal and cause rust to form, were not lost on me. Seeing the scalped cab makes me think that there's so little room that it almost wouldn't be worth the trouble. I can sympathize with the black and the heat, because that's what I'll have to live with when my truck is done.

[tonypaul]

I found this:http://www.subrosa.com.my/automotive_foam.html and
http://www4.shopping.com/Evercoat-Ma...lant-Foam/info

Not sure how it differs from the kind of spray foam you get at Home Depo....

[dznucks]

They make a foam for windows and doors that does not expand and stiffen like the great stuff. i just used it when i replaced all my windows in my house. the stuff is still soft after several months.
I got it at home depot.

if i was going to try it, thats what i would use. i am curious how this goes. its crossed my mind before.

[ChevLoRay]

Lizard Skin is a spray-in insulation that may work well in this app. Yeah, I hear it is expensive, but it's an automotive product that is supposed to be very, very good at insulation properties for both heat/cold and noise.

[POPO1984]

You must have watched Powerblock this weekend... I did too

Originally Posted by ChevLoRay

Lizard Skin is a spray-in insulation that may work well in this app. Yeah, I hear it is expensive, but it's an automotive product that is supposed to be very, very good at insulation properties for both heat/cold and noise.

[mbgmike]

I work for Dow chemical and we make a lot of the products used by Ford,GM and Chrysler.(I work two full time Jobs) Also the foreign ones too. Betafill and BetaFoam are trade names of Dow products that they use. We have listings on which vehicles they use it one. Some vehicles they will use another brand but most our Dow. The problem is they will not sell retail unless you buy in tank cars. You will have to go to a wholesaler to purchase. It has anti-corrosion additives and even can be painted over and does not absorb moisture.





here is a link to some descriptions
http://www.dow.com/PublishedLiteratu...romPage=GetDoc

http://www.dowautomotive.com/capabil...y/betafoam.htm

http://www.dow.com/PublishedLiteratu...romPage=GetDoc

YouTube - BETAFOAM Foam Technology by Dow...

A lot of the companies will package the products under their own name but these are what the products are. They all buy them under their own product code the resell with their name on it. The stuff works

[mbgmike]

Originally Posted by dznucks

They make a foam for windows and doors that does not expand and stiffen like the great stuff. i just used it when i replaced all my windows in my house. the stuff is still soft after several months.
I got it at home depot.

if i was going to try it, thats what i would use. i am curious how this goes. its crossed my mind before.

Great Stuff is a Dow product. They make many different types for diff applications. Great stuff was not meant for Autos.

[dznucks]

How would you go about finding a retailer that would sell to the average dude?

[capev86]

i would go with lizard skin or some kind of poly bed liner to coat the backsides of the sheetmetal. you don't want to block the cavity, just muffle the vibration of the panels. they showed how well poly bed liner absorbs explosive energy on mythbusters. and it won't let moisture get under it.

[MAK191]

what about this stuff

http://www.autobodytoolmart.com/3m-a...8-p-10857.aspx

or

http://www.autobodytoolmart.com/3m-a...3-p-10858.aspx