I was wondering if anyone has used a product called "R-Tech" made by Inslafoam. I was looking for Homasote but it is difficult to find, and saw this product in the local lumber store. I would use it between the 1/2" cookie cutter plywood and the cork roadbed.
I'm new at this so any help will be appreciated.
This appears to be a housing insulation product that is also used by hobby modelers. Comes in various thicknesses, is very cheap and available at Lowes and Home Depot.
I did a Google on this and got lots of hits from advertising to technical to practical.
I use Sound Board, which is a compressed fiber sheet similar to Homosote that is made from sugar cane and other vegetable matter. Nearly all of the building supply stores here in Arizona carry sound board in 1/2 inch thick sheets. Look in the insulation section for a brownish-colored 4x8 foot sheet of Sound Board. I think it is easier to work with than Homosote.
I have never seen or heard of R-Tech, but from their web site it is described as a very dense foam board.
http://www.r-techinsulation.com/home.html