Kale

First, Asphalt products are significantly poorer performers than butyl products (Raamat, SecondskinAudio, newer Dynamat.) This is both in damping and adhesion performance.

Second, and most importantly:


Do you really want to sit in an enclosed box surrounded by toxic-vapor leaking fumes to save a few cents per square foot?



Update from Fatmat:

(see below, brought this up to the top to make sure things are accurate.)

RandyJ75

Wow Kale, that is amazing. Thanks for posting the info.

Glad I used Raamat/Second Skin.

y2kylwc5

What products do you recommed?

SublimeZ

http://www.sounddeadenershowdown.com/

Kale

As far as I'm concerned, only 3 products exist for damping: Dynamat, Raamat, and Second Skin.

Dynamat Extreme is very good, and is very expensive.
Second Skin Damplifier Pro is better than Dynamat (by user accounts) and cheaper.
Raamat is the budget choice, being a lighter material, messier butyl and thinner foil layer - but significantly cheaper.

EVIL_C5

this is what I got back when I emailed fattmatt about this.

Hello Brian, this material is not dangerous and the information that is in that forum is talking about the asphalt that you would find on the road. What he neglects to say is that there are different kinds of asphalt which are made with different ingredients. Fatmat for instance has absolutely no hydrogen sulfide. The asphalt that is used in road construction does give off fumes because it is heated to the point of being in a liquid form which releases those vapors. As I am sure you know fumes and odor are completely different. The FatMat is mainly a rubber mastic with a asphalt mixture which is used for the adhesion. The only reason it has an odor at all is because it comes straight off the press and is sent to you.
During installation if you have sensitive skin it may cause skin irritation, so it is a good idea to wash up after the install, however that is not common
We have had this product tested and as long as it is not eaten but is used for its intended use it has no health effects.

Kale

This is good news. But in any case, butyl is the stuff to get for damping. I updated the original post with this information.

pcfred

I used Fatmat in my truck last weekend and it still smells like asphalt, I called them and they said it should go away in a week or so but I really wonder. I left the rear windows down a couple inches for 2 days and the smell has lessened but after the truck sat yesterday with the windows up the smell was definetly still there. So now I'm thinking of ripping it all out, washing down the interior and using a different brand.

Kale

Damn. I'm sure it will go away eventually. Or you'll get used to it..

EVIL_C5

when I did my truck with fatmat, it took a week or 2 for the odor to go away and I put almost 100 sq feet in it.

RichDash

I have used all mentioned products. In small and large quantities. To be 100% honest i could never tell an audible diff in any of them. At this point in time i now use fatmat due to price. It takes a month to get it shipped to you but it does as well as the others. The website posted above is actually hosted and done a while back and many people feel its absolutely biased. It really wants to sound scientific but it was funded and done by someone who had interest in the product. I really encourage anyone who is going to do this to seek out people who have done extensive projects with the materials and see for yourself. Use a heat gun and j roller from home depot and your fine, just have a ton of razor blades on hand cause they tend to gunk up fast. Also dont forget that fatmat weighs much less then some of the other mats. I personally dont want 200lbs of sound deadener in my sports car. As far as smell goes... They all smell like crap... it goes away though. and no i have never had a car yet that i used fatmat on suddenly have all the material fall off. I have done it to many cars and my own personal cars i have used fatmat on are a Jeep ZJ, two f-bodies, tahoe, 3000gt, grand prix and a old caddy. plus at least ten friends cars. I have used it much more then second skin or dynamat or raamat for cost reasons but done full installs of all ranging from 10 feet to several hundred feet. have fun with your projects but dont read too much into the hype...

pcfred

I used Fatmat and the smell lasted almost 2 months, matter of fact I can still smell it a little some days As far as effectiveness, it did a good job, I can definitely tell the difference in sound. I used Dynamat in my other vehicle, it did the job and NO smell at all.

Kale

Real butyl mats have no noticeable smell at all, unless you're literally sticking the mat in your nose. They are also incredibly more effective at lighter weights than asphalt. Asphalt is just a mass loader... butyl provides viscoelastic damping. This is the reason why all quality deadening manufacturers have switched to butyl. And Raamat is hardly expensive...

And as far as fatmat goes, I wonder what the deal with this story is...
Funny that asphalt-peddlers would try to pass it off as butyl...


In any case, for Corvettes specifically, I'm thinking that damping mat in general is not the best material to use... And perhaps a type of liquid damper is, such as Spectrum Sludge. They don't really 'ring' like metal panels do.


Also this link is interesting:
http://www.diymobileaudio.com/forum/...9&postcount=31

Particularly:

VerTigo456

I was told that the E3 liquid deadener in conjunction with the cowboy insulation kit was a great choice. Any suggestions or recommendations? About to do this mod on my car myself. I know I would probably want something else for the doors?

Kale

edead liquid dampener is decent stuff, it needs to go on THICK. I used it in my C5.

IF you want to wait for a while, I have some Second Skin Sludge on order, and I can directly compare the products.

cowboy kit is great for heat and high frequency noise (ie will take the edge off tire noise.)

you need straight up mass (like luxury liner) to block anything in the lower road noise area.

VerTigo456

Cool...thanks for the heads up. When are you installing the Second Skin Sludge? What would you advise for the doors?

Kale

I think the doors need to be stiffened more than they need to be damped... I'd reinforce them with something.

Smooth72

Maybe overkill, but in the door I used damplifier pro on the inside of the door outside of the door and the back of door cover. I also used luxury linear on the inside. I also sealed up the large open in the back of door with plexiglass and covered it. Here is my build look at post 40.
http://forums.corvetteforum.com/show....php?t=1932059

VerTigo456

Thanks for the advice...waiting to hear back about how second skin sludge it does sound like second skin is the way to go. Saw your car...fantastic looking! great work...

Smooth72

Used the sludge on a 69 pickup and it worked great but have not used it on fiberglass yet. I plan on using it on my 72 vette in addition of the rest of the sound proofing.