On doors, do you apply a dynamat style sound deadener to the inside of the outer shell or the outside of the inner shell, or both? I've seen/heard that you don't need to wallpaper the entire surface, but that a few strips and patches will kill alot of the empty-drum resonance. Any experience or advice here?
The outer skin is the part that resonates like a drum. Even a little bit makes a big difference: I stuck a tiny free sample of dynomat extreme (about an inch square) on the outer door skin of my bare '53 Chevy door and was stunned how much difference it made. Seriously. I also added some to the inner skin and it made no difference. I ***ume all the ribs already keep it from being the source of the problem.
That's been my experience. I think the stamped shape of the inner skin keeps it from being so resonant. And covering the inner skin would make the door awfully heavy! If I understand correctly from some searching I did a few months ago, you only need to cover 1/3 of the inside of the outer skin to deaden it as much as it can go. Then you want something to absorb road noise (like a layer of closed-cell foam) that can be on the inner skin if it's easier that way. Hopefully some acoustical engineers can pipe in on this?
A litte bit definately goes a long way. We were finding structural cracks in fairings on a particular model of jets even after replacing the cracked structure with new pieces. We decided to stick strips of 2"x4" and 2"x6" tiles (similar to dynamat but with a higher heat resistance) to the inside of the fairing skin to reduce vibration/resonance and problem with reccuring cracks was fixed.
Some interesting stuff here off a thread on one of the truck boards. http://www.sounddeadenershowdown.com/cgi-bin/index.cgi?p=pr He doesn't say anything about heat insulation though.
I used DynaMat on the entire outer door skin and then sprayed Lizard Skin on the inner door frame. QUIET !! It is really helps with the heat/cool. My A/C will run you out of the 3W on low.
I can attest to the fact that this stuff works great for heat, but for vibration and sound you need a heavy dampener like the dynamat extreme.
Since for much less $ you can completely cover the entire surface with ours opposed to just putting in a few squares or strips of others and get pretty good sound deadening. Sure covering the entire surface with a product like Dynamat will give you the best sound deadening but you could several hundred bucks to do this. No its not and that's another reason that the price is so low. We recommend using a spray contact adhesive such as 3M General Trim adhesive #08088 or Super Trim Adhesive #08090 when it needs to be adhered to the surface. Personally I dont like to glue it or anything else to the floor. On the cars I do I do some cutting and splicing with aluminum tape so it will conform to the shape of the floor then just lay the carpet on top of it. Heres a pic of the floor on my company car where I did this.
On a fairly full-panel door like my '50 has, I Dynamatted the inside of the outer skin as well as the inside of the inner structure (the part the interior handles mount to). Sounds like a Kelvinator when you close the doors.
Just to clarify, I insulated the floor and roof and firewall of my '53 Chevy with the low-e that EZ Cool is selling and I am happy with it. It is lightweight, easy to use, and does an excellent job of blocking heat. My car went from being a sauna to being comfy. I'm just saying that although it does block noise somewhat, it cannot dampen vibration the way a heavy peel-and-stick product like Dynamat does. They just work very differently. A few sheets of dynamat extreme placed here and there will deaden most of the vibration and resonance in a car, and then covering it with a continuous layer of a product like the low-e will block the heat and help to further reduce the noise. Dynamat by itself doesn't do much to block heat and the low-e by itself doesn't do much to dampen resonance. Together it's a pretty *****en combo.
atomic, appreciate your comments. I'm looking for something that will help with resonance and overall sound.
If you look inside the doors of Cadillacs and other expensive cars you will see a piece of sound deadening material a foot square or less glued to the middle of the door. This turns the *klang* to a *thunk* when you shut the door. They go to a lot of trouble to get cars like that as quiet as possible.
I used this and was "VERY" happy with it. http://downsouthb***productions.com/at/index.php?option=com_virtuemart&Itemid=57&vmcchk=1&Itemid=57
Factory / traditional method (at least on late 30's Mopars) is 1/2 inch thick asphalt/ tar slapped messily on the bottom of the inside of the door skin. Hard to remove 70+ years later.
So does the "flashing" I bought at Lowe's. The standard stuff is asphault, and the deluxe stuff is butyl rubber.
Went to Lowes and looked and all they have here is rubberized asphalt flashing. The butyl flashing must only be available in certain areas. Thanks for the info, wish Lowes had it here
If you know the product, brand, part no. etc please post it up. It might be a Lowes elsewhere could order it. As a guess, butyl may be a northeast only option.
It's called peel and seal... Works really well at a fraction of the cost of DynaMat but dont let anyone else know. Read the reviews of this product and it might shed some insight on the application. http://www.lowes.com/pd_154017-81326-PS625_?PL=1&productId=1018733
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