Polyfil vs Closed cell foam vs gym socks. Sound deadening question, yay!

[HomeLite 10+ year member]

What's up peeps?!

I have a question that has been weighing heavily on my mind for awhile now...

I want to make my noisy car slightly.. er... less noisy. Including but not limited to: reducing any noise from the outside world, less rattles, better sound inside the car ^_^.

So, I'm going to use a certain rubber and aluminum product that comes in sheets for sure. I'm not going to mention a brand because I don't want this thread to be a flame war. Eg. If I said I was putting in Dynamat, someone would say that I should have gotten Second Skin. Or if I got Second Skin, someone would say to get Dynamat. Or If I said I was putting in Peel & Seal, someone would say to get... anything else.

But that is not what my question is about. I would like to know what I should put in the space between the metaly-rubbery sheets and the car. I drive a Matrix so my first example will be of the hatch. What would be good to fill the big space in between the frame and the outer wall of the hatch? I've seen people spray closed cell foam or polyfil to fill the space.

I'm a bit scared of the spray foam stuff because of its permanency. Also since there isn't going to be any moisture in that cavity, what about stuffing the area with old clothes or something?

What about in between the door frame and the skin? I'm just looking for something that will fill up these voids for the cheaps! Points for creativity

Click to read more...

 

[Nut Hair Trick 10+ year member]

I sprayed my trunk lid with that great stuff foam, put a little Audio technix on it. and it is HEAVY AS HELL! It seriously feels like it gained 20lbs and I didnt do much to it. I personally love the spray foam stuff, or you could use polyfill, but be prepared to sit there all day doing it.

 

[JimJ 5,000+ posts]

I've found that wearing the gym socks several weeks in a row before using them provides a cleaner, more natural sound.

 

[Imtjnotu 5,000+ posts]

I've found that wearing the gym socks several weeks in a row before using them provides a cleaner, more natural sound.

holy **** jim where the fuck have you been...you havent posted in ****** months

 

[JimJ 5,000+ posts]

Don't worry, this is a mirage. I'll disappear for a few more months //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 

[Louisiana_CRX 5,000+ posts]

Don't worry, this is a mirage. I'll disappear for a few more months //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

//content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif

 

[bubbagumper6 5,000+ posts]

Phone books are free and easily obtainable plus they would make the panels bulletproof too //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif

 

[kmanian 5,000+ posts]

go buy a cheap memory foam mattress topper, cut it up and stuff it in there. then go to your local roofing contractor supply house and get some 80mil EPDM rubber roofing and use it as a cheap replacement for mass loaded vinyl, make sure the are no cuts or holes in the EPDM when you are done, a double layer of EDPM will be better if you have the time and patience.

 

[Dirtrider4eva 10+ year member]

this ^^^ x1029403946456456345

 

[whitedragon551 5,000+ posts]

First of all there is science behind not using Peel and Seal. Im not going to get into it, its been beaten to death in recent weeks.

Deadener is used to change resonant frequency of a panel causing less vibrations. If you want to stop rattles between panels then closed cell foam (CCF) is the proper item to use. If you want to keep sound in and road noise out mass loaded vinyl (MLV) is the proper item. Its that simple.

 

[whitedragon551 5,000+ posts]

go buy a cheap memory foam mattress topper, cut it up and stuff it in there. then go to your local roofing contractor supply house and get some 80mil EPDM rubber roofing and use it as a cheap replacement for mass loaded vinyl, make sure the are no cuts or holes in the EPDM when you are done, a double layer of EDPM will be better if you have the time and patience.

Except EPDM isnt mass loaded and memory foam mattress material is a poly foam and isnt closed cell.

 

[Dirtrider4eva 10+ year member]

for a cheapo idea it works. not the best. bet ya.

 

[whitedragon551 5,000+ posts]

for a cheapo idea it works. not the best. bet ya.

It doesnt work. The science behind it proves otherwise. For a cheapo idea Peel & Seal works as well, but in reality it doesnt.

Use anything but closed cell foam in a door panel. When it holds moisture and electrical components rust and speakers get wet you know why.

 

[audioholic 5,000+ posts]

I'll disappear for a few more months //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

Just try changing your gym socks once in a while during that time, k? //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif Good to see you again Jim.

 

[audioholic 5,000+ posts]

Closed cell foam wont hold water, because the cells are closed. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif Its open cell foam (more common than closed cell) that will act like a sponge. But yes, even using closed cell foam can create a situation in which water can be trapped and held between the foam and metal, causing rust. This can be avoided by making sure the foam is in full contact with the sheetmetal.