I'm sure this has been referenced before, but one alternative to dynamat
is B-quiet  http://www.b-quiet.com/
They also sell spray-on sound deadining 'paint'

Todd
'88 Westy

Holly and Chris Mills wrote:

> I hope this bit of info helps some of you and it applies to anything old
> and noisy.
>
> This vehicle in question is a '78 VW Westfalia camper. I'm finishing a
> general freshening up - that has taken 2 years this Easter - which includes
> trying to update a few things - the upholstery, interior lighting, noise
> level at 60 mph, and handling (with sway bars).
>
> I started a hunt for a way to quieten it down. VW's are pretty noisy
> sometimes of course.
>
> The search naturally led to Dynamat but the cost was way to high for my
> budget to support enough material to do this bus which has lots of floor.
>
> JC Whitney had their version of Dynamat as a reduced cost but still high.
>
> My objectives were to lower the noise inside the van:
> 1) cheaply
> 2) effectively
> 3) not create a rust problem (the VW can do that on it's own)
> 4) I wanted something that I could get locally (in our small town)
>
> Dynamat fails #1, the silvered faced sheets of jute that Lowe's sells
> locally fail #2 as their isn't enough material (thickness) there.
>
> Carpet underlayment fails #3 I guess and so may industrial neoprene (also a
> reasonable cost).
>
> The various OEM guys use a thick tar paper material much like Dynamat on
> the fire walls and some parts of the floors. All that LOWE's has to offer
> was thin tar paper - which would require may layers of glue and paper to
> build enough mass to be effective.
>
> A fellow once posted to one of the VW lists that there are two basic ways
> to dampen the noise a car makes - absorb it (upholstery, carpet, etc) so
> there isn't much to reflect, or dampen the vibration of the metal panels of
> the bodywork. The OEM guys use a combination of both obviously using the
> tar paper panels and jute. I'll do the same with my asphalt material on the
> floors and foam on the vertical surfaces all - and I mean all of the other
> surfaces upholstered - roof too (all except the cabinets).
>
> Finally I started talking to local roofers - specifically ones that worked
> on commercial flat roofs. One very helpful fellow here in middle TN took
> the time to show me the materials he uses which were mostly as you can
> imagine, the standard thin tar papers.
>
> However he showed me a roll of modified polymer+bitchum - that is 180 mls
> (maybe a lower number slightly) versus the thin regular tar paper stuff.
> Imagine comparing sliced American cheese to newspaper.
>
> He showed me how it had a face which when heated with a Propane torch would
> get sticky and could be layered to any thickness. It looks like three
> layers would gain you 1/2" or so. The heat required seems to far exceed the
> temps of a hot car in the summer.
>
> It will also require a torch to really get this stuff contoured to any
> curves your floor might have. I left the roll of material in the back of my
> CR-V for two days (other things to do) and noticed no smell despite the
> fact the car got 70 degrees one day (inside) and feel confident that any
> very hot days my bus might see would only create a small stink inside that
> would fade with time.
>
> My plan is to lay this material directly on the floor with glue and heat
> and then top it with any layers I might need and then top it (and glued)
> with the silvered jute material from LOWE'S to keep the black
> bitchum/polymer junk where it belongs. This will be topped with carpet and
> etc.
>
> A roll 3 feet by 45 feet cost me $42. The opposite side of the material is
> similar to regular tar paper but not prone to tearing - in fact you
> couldn't if you tried.
>
> It weighs about 50 lbs for the whole roll.
>
> He questioned me to the exact trade name of the stuff in the magazines
> (Dynamat) and told me he was sure that Dynamat was a 'John Mansfield Co'
> trademark and was generally used (as I understood it - our conversation was
> held during a hard rain under a tin roofed pavilion) for walk mats in
> roofing - sections of flat tar roofing with a thicker membrane suitable for
> foot traffic (maintenance people). It was also cheap and very similar to
> what I purchased - naturally he had my stuff in stock and didn't have the
> raw Dynamat though he said he could get it if I wanted to wait a few days.
>
> So looks like the magazine guys are making a fortune off of folks willing
> to pay retail price for Dynamat. My version won't have peel and stick glue,
> so I'll have to use spray can glue I think, but I am very excited about a
> successful hunt!
>
> Hope this helps some of you out there.
>
> Two successes this week - another fellow on the Type 2 (VW) list sent me
> the recipe for Waxoyl (another item sold in small quanities through the
> catalogs) - anyone know where I can buy candle wax or bee's wax in bulk?
>
> I'm getting a good education from you GOOD folks!
>
> CHRIS in Tennessee
> scmills@tntech.edu
> ICQ: 5944649
>
> '78 VW Westfalia (maybe some CIS injection,Corvair, turbos --- maybe I'm
> just dreaming.....)
> '65 Beetle (Type IV powered)
> '99 CR-V 5 speed
> '49 Chevy 3100 Pickup
> '81 Honda CB900C