Sound deadener might fall off..recommend some glue to keep it up?

[audioholic 5,000+ posts]

Someone said aluminum backed foil has superior noise rejection. Why is that? You mean the aluminum on some of the products actually serve noise reduction purposes?

Yes, that's its ultimate purpose on the mat. Its a secondary layer of another material with much denser properties than the rubber to serve to help block sound waves the rubber would otherwise pass through.

 

[Tonyguy 10+ year member]

One guy i work with had some brown bread in the doors of his 06 civic. That stuff melted one day and ruined the beige interior. So it does indeed melt at a certain point.

 

[Rudy 10+ year member]

Someone said aluminum backed foil has superior noise rejection. Why is that? You mean the aluminum on some of the products actually serve noise reduction purposes?

That's correct - in two ways. Butyl andhesive and high quality liquid dampers work in several ways, but one of the important ones is through viscoelastic damping - internal stresses in the adhesive react to deformations caused by vibration and convert some of that energy into heat. Adding a foil layer, and the heavier the better, enhances this by becoming what is called a constrained layer viscoelastic damper. Heavy foil is required, the Mylars and Myalr with 1 mil foil are really useless for this.

Second, these products act as barriers - blocking sound from passing through the substrate to which they are attached. Here, again, a thick foil will work better.

 

[Rudy 10+ year member]

One guy i work with had some brown bread in the doors of his 06 civic. That stuff melted one day and ruined the beige interior. So it does indeed melt at a certain point.

Even when fresh and new, asphalt products will melt somewhere around 180°F. Most of us assumed this was a very extreme temperature that wasn't likely to be reached except, for example, by a black car parked in the sun, during the middle of the day, in Death Valley - or something close to that. Those assumptions were based on measuring the air temperature in the vehicle. Hard to get the air that hot, but that isn't where the deadener lives.

I've measured temperatures just reaching 180°F in the dark gray trim panels of my light silver Civic after a few hours in the sun, using an IR thermometer. This goes a long way toward explaining why so many people have had catastrophic failures of asphalt mats despite the claims of unscrupulous or ignorant sellers that the stuff was "high heat tolerant".

Something I forgot to mention in an earlier post is that because asphalt is not very sticky or flexible unless it is quite warm, the normal instructions are to use a heat gun to install it. You can melt the asphalt in less than a second. It will harden back up, but the very act of heating it accelerates its deterioration.

 

[Rudy 10+ year member]

Yes, that's its ultimate purpose on the mat. Its a secondary layer of another material with much denser properties than the rubber to serve to help block sound waves the rubber would otherwise pass through.

Sorry, audioholic - don't mean to keep stepping on your toes, we're posting at the same time //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[audioholic 5,000+ posts]

Sorry, audioholic - don't mean to keep stepping on your toes, we're posting at the same time //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

No worries, I usually just shut up and listen when you discuss sound deadening anyway. lol //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

All that visceo-mumbo-jumbo talk you have, hell it was much better than my reply anyway. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif