How does new stuff like hushmat and dynomat compare to the old rubber tar underlay (I'm not sure what they were made out) that were stuck to the floors of cars in the 60's and 70's? Does the old rubber stuff have any advantages?
I'm laying down some Dynamat now for the first time. Can only go on what the manufacturer claims as to its effectiveness. However, after pulling up the old underlayment I suspect the Dynamat will be a major improvement. Ain't cheap but I've read some posts of folks using similiar type products from home supply stores that they felt worked pretty well too. I may consider that in the trunk area.
Have Dynamat in my avatar, installed nicely and makes it water tight, used foil tape on the seams. You can go online and buy Dynamat look a like underlayment for a lesser price, have used some of that stuff as well and noticed no difference in quality. And I almost forgot, welcome to the HAMB!
The old "jute" padding is still available at most good upholstery wholesale suppliers..sold by the yard...
Do NOT use the jute backing, it holds water against your floors for almost 2 weeks after it gets wet. I suggest a truck paint in bed linner type product. You need something to seal the metal and keep the moisture off the floor pan. Floors rust out from the top/inside down. Gene
Are you looking to deaden panels that are resonating, or are you looking to block out road noise? Dynamat's intended purpose is to suppress panel vibration, while absorbing some road noise. And contrary to popular belief, does not require 100% coverage to be effective. 30-50% is sufficient, when applied in the correct locations. If you want a true sound barrier, use a layer of MLV (m*** loaded vinyl) over the dynamat. Its black rubbery mat about 1/8" thick, and it's heavy! Approx 1 lb per sqft. The stuff from Home Depot isn't bad, but a lot of people report it off g***ing (fresh tar smell) when it gets hot in the sun. (I've never used it, so I can't comment 1st hand) Check out KnuKonceptz for their Kno Knoise deadener, it's cheaper than Dynamat, and just as good. http://www.knukonceptz.com/mobile-audio/sound-deadening/kno-knoise-resonance-control/ Fatmat is another budget friendly alternative to Dyn. https://www.amazon.com/s/?ie=UTF8&k...&hvtargid=kwd-24903083&ref=pd_sl_5w9a18aigr_e Secondskin has very nice products, but they're not cheap. http://store.secondskinaudio.com/damplifier/ MLV link; https://www.amazon.com/Loaded-Vinyl...=1427585168&sr=8-2&keywords=m***+loaded+vinyl
More info in this thread: http://www.jalopyjournal.com/forum/threads/best-sound-deadener.977364/#post-11418769
I am a big fan of m***-loaded vinyl. I have a big roll of it, in 1/4", that I have to move with a forklift. It only needs to be adjacent to things that make noise. Elsewhere it is wasted, and just adding weight. It is seriously heavy. I put it over 1/8" closed cell foam, and that over Fat Mat, for a luxury car like quiet. Above all of that, thinner than normal (to make room for everything underneath) carpet padding and carpet. You can still annoy the neighbors, without losing your own hearing!
As someone who drives their old iron every day, these are real concerns for me. I've even been concerned that the paint-on bed liner could loosen and hold moisture-like a lot of old undercoating I've seen. I use a rubber truck bed mat on the floor against the steel Those heavy mats have little bumps that hold air gaps along the steel. They don't conform well to curves, but they work great on flat floors. You can put a carpet or rubber mat on top of them and they hold the sound down pretty well.
I used Fat Mat on my Ford. My buddy who helped put it down said it was more flexible than Dyna Mat and 1/2 the price.
I used the stuff from lowes used for wrapping around windows of a house. Twenty bucks a roll and it sticks like mad. I think I used two and a half rolls, Double on the firewall.
I don't suppose the "old stuff" had/has any advantage unless you're a purest building a museum piece. The "new stuff" has the advantage of newer tech and material, and probably not as messy. The aluminum foil probably helps a little with temperature insulation, too.
After doing some research I believe this to be about right. I don't know that the newer stuff is any better at sound deadening, but it seems that both old and new is butyl rubber based. I thought the older stuff was possibly better because it was heavy and/or more dense, but looking on Dynamat's website they have some thick 3/8" stuff now as well.
That's not peel and stick butyl based panel deadener, that's a thermal and acoustic padding for under the carpet. It's a hybrid of MLV and closed cell foam. You can use that, but you may still get panel resonance (that tin can sound). You're best bet is to use 30-50% coverage of Fatmat and a complete coverage layer of the MLV I linked. Please note that normal adhesives will not stick to MLV. Weldwood Landau top and trim contact cement, is highly recommended.
That's the stuff: http://www.dap.com/dap-products-ph/weldwood-landau-top-trim-high-heat-resistant-contact-cement/
The Knu Konceptz I linked offers two sizes. 80 mil and 100 mil. Obviously the 100 is more expensive. Pretty sure Fatmat offers similar thicknesses.
80 mil is 2mm thick or .078" so yes the 100 is about .100". Coming from a Compe***ion Car audio back ground, I can't think of too many times I've had to use a 2nd layer, because the first layer wasn't effective enough.
I used Dynamat throughout my coupe. I added the 3/8 thick foam product on top of the Dynamat on the firewall. I am very happy with it. Except my noise sensitive wife is complaining that she can hear the odometer turning over in the speedometer............ That how quiet it is. Probably should have used shorter mufflers to compensate.
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