Thread: Sound Proofing

i would rather use rubber sheets......as they wont absorb moisture like foam does.......

otherwise.....it sounds like it might work.......even on a fender......

Originally Posted by DEFENDERZOOK

i would rather use rubber sheets......as they wont absorb moisture like foam does.......

otherwise.....it sounds like it might work.......even on a fender......

Yeah I was sort of thinking using rubber instead of foam. but i think a closed cell foam would be ok


Ha ha Fenders are whisper quiet compaired to my SIII

Originally Posted by paulthepilot_5

Hi All,

I've just been reading some of the old threads which cover sound proofing of Landys. I was looking at making my own sound proofing material by sandwiching some thin lead sheet approx 1mm, in between some thin sheets of foam rubber. would be alot cheaper than most of the sound proofing products on the market. What are peoples opinions on such a method?

Cheers
Paul

Strange as it may seem, I am trying this out at the moment. I have made a bell housing muff for the 110 to try and cut out some of the clatter at idle. It comprises a sort of envelope of heavy plastic sheet (started life as an advertising sign) containing an inner layer cut from a hiking mattress about 10mm thick dense foam, and an outer layer of a sheet of lead from some old flashing. It is secured by ropes tied round it every 5cm and passing through eyelets in the middle join and end.

Results are positive so far, but we will have to see how durable it is. Also, there is a considerable gap at the bottom I want to block off, so I will probably rehash it when I get back from Perth.

The big problem with anything using sheet lead will be keeping it in place, due to its weight and structural weakness, but in this sort of position it may well be suitable. I can envision all sorts of problems with it, for example, as an under bonnet insulation.

This sort of insulation acts by blocking the transmission of sound through the foam/lead interface, where it will be almost totally reflected due to the big difference in acoustic impedance.

John

interesting timing, as I'm thinking similarly - although for cost/weight/convenience i was considering painting a closed-cell foam layer with bitumen paint, then possibly sandwiching another layer... assumes the bitumen paint remains flexible enough.

I was originally considering the bitumen/felt products available, but after leaving the fender out in the gippsland rains on the weekend, the temporary felt in the footwells was saturated enough to make me think twice about anything that holds water...

Nylex used to make a variety of noise absorption and noise barrier products. Closed cell foam with a reflective foil layer, closed cell foam and lead sandwich, etc. All are used in their appropriate application. I had a fair bit to do with this stuff when the mining coys and unions got fussy about noise levels of mobile plant. Find a source on the internet or yellow pages and ask for recommendations. The foam/lead/foam sandwich was the most effective and most expensive but needed to be in the right places.

Originally Posted by Brian Hjelm

...Find a source on the internet or yellow pages and ask for recommendations. The foam/lead/foam sandwich was the most effective and most expensive but needed to be in the right places.

I don't know how many people watch Foxtel programmes like "Overhauling" but they always use a self adhesive black/silver foil backed mat product called "Dynamat" I think. Am assuming it is some sort of closed cell/bitumen/lead product.

Does anyone know of an Australian distributor?

Diana

The foil facing reflects sound, the foam absorbs sound, and the lead is a barrier. We found we had to use all three in appropriate places according to the build and nature of the machine concerned.

Try a marine product called "Sound-sorba".

Used in fancy motor-yachts, to insulate engine boxes etc, it is heat, oil, water-resistant. Comes in a variety of thicknesses, can take to curves, and is glued or screwed into position.