$3k on soundproofing a defender!? :o .. dynamat and?Quote:
Originally Posted by granno
Printable View
$3k on soundproofing a defender!? :o .. dynamat and?Quote:
Originally Posted by granno
http://flic.kr/p/eeQGxYThis was most of it.. There was a lot of dynamat, but i keep running out. All the dynaliner I have is 1/2" and is too thick in some areas. So I ordered another 2 x 1/8" 2 x 1/4" and another dynamat pack.. Oh and a roller - bit late for that now but the hours I have spent rubbing every square inch of it with makeshift shapes.. Never again..
That dynapad is not cheap
Anyone done a before and after with a db meter?
Hang on there. Dynamatt is not a heat insulating material. It is a deadener.Quote:
Originally Posted by granno
You don't need to "cover" anything with dynamatt. Just patches in the middle of panels to kill the resonance. If you've spent $3k on the stuff then you've wasted about $2,700 of that.Quote:
Originally Posted by granno
Camping mats are EVA foam. This is the best insulation layer to go between your deadened panels and the top cover. But the 10mm matts are quite stiff and will only do flat surfaces. You can buy it down to about 3mm thick from industrial suppliers quite cheaply. 3x 3mm layers will give you better sound and heat insulation than 1x 10mm layer.Quote:
Originally Posted by DeeJay
Then you want heavy rubber or vinyl over the top.
Hmm the dynamat extreme that I put on my floors and firewall significantly reduced the heat from the engine and exhaust. Prior to fitting on a long drive it felt like you were in front of a slow combustion stove. It was so hot that driving up the blue mountains once at night in winter I had to open a window! (heater disconnected)
Post dynamat (all surfaces - see build thread for pics) there is hardly any heat. I know on paper that isn't what its for but I'm talking real world drop of 15+ degrees.
A layer of anything (even well conducting gold) will reduce heat through to the cabin.Quote:
Originally Posted by flagg
But using Dynamat for that purpose is like buying goldfish for cat food.
EVA foam is far cheaper and far better. Small patches of a deadener (dynamat if you prefer that brand) and full cover of EVA foam will reduce heat and noise far more for a far lower cost.
Well I got a rush of blood and down loaded a db app on the iPad any how with the iPad sitting on the pasenger seat at idle 52db a quiet room is about 45 db at 100kph its around 63 to 65 db It peaked at 71 db when I realy stood on it in 4th to merge on to a busy road. The vehicle is a 110 tray back 300tdi with just the factory rubber mats and that vinyl crap around the front of the seat box and a gq patrol centre console
Bitumen backed reflective foil (esp on the hot side) is actually very good at keeping heat out. There are cheaper brands than dynamat. Full coverage of bitumen foil is the way to go if you want a very effective block on heat transfer using a thin substrate that will bond for good. You will find it very hard to get the same coverage and bond with camping mat on anything other than floors.Quote:
Originally Posted by Dougal
I went around the Med without a headliner and I could burn my fingers to a blister if I touched the inside of the roof after it had sat in the sun. I covered the roof completely with a bitumen backed foil that is thinner than dynamat extreme. Tested in the same conditions I could touch the foil and feel only a vague warmness! Combined with tinted windows, the difference to temperatures inside the car when left in the sun was well worth the £40 it cost for the bitumen sheets (UK)!
[QUOTE=Dougal;1902802]Hang on there. Dynamatt is not a heat insulating material. It is a deadener.
Yep.. Tried the dynamat first and found it next to useless for heat. Then I did a lot of research.....
The rest of the money was for dynaliner for the heat. I also purchased dynapad which was the most expensive out of the lot for the floors/firewall, seat box and gearbox cover. I also used the Hoodliner for the bonnet, and re did my acoustic cover for the motor. Instead of carpet I am using a super high density vinyl in the cab area only. That roll alone was about 30-40 kg.
The thermal conductivity of materials is measured as a K value. Watts x metre. Which is actually w per metre squared per metre thickness.Quote:
Originally Posted by manic
Lower values are better insulators.
From there, to account for insulating thickness, you divide the K value by the thickness and that gives you watts per square metre (u) of material per degree of heat difference. The often referenced R value is 1/U. Lower U (hence higher R) are better insulators.
K value for bitumen, 0.17. Thermal Conductivity of some common Materials and Gases
K value for EVA foam, 0.033 Polyethylene and EVA Foams
So for equal thickness, EVA foam is ~5 times better.
But we aren't talking equal thickness, we're comparing 1mm of bitumen to at least 6mm of EVA foam.
Bitumen: 0.17/0.001 = 170 watts per degree of heat difference per m^2.
EVA Foam: 0.033/0.006 = 5.5 watts per degree of heat difference per m^2.
As a thermal insulator, 6mm of EVA foam is (170/5.5 =) 31 times better than 1mm of bitumen.
With EVA foam you'd have saved heaps, had a quieter vehicle and a far cooler one.
BTW, you don't want to bond your insulating materials as that greatly reduces the thermal and acoustic properties. Every air gap is worth an R value (1/u value) of ~0.2 for thermal insulation.