I was thinking if using this as a base under my cork/track to raise the track. Question is it strong enough (single layer) or will it settle over time? Ill be running some fairly heavy locos so ???
More info. It will be laid on 1/2" plywood .
Are you wanting to just put it under your track roadbed or over the entire plywood base? Not sure why you would want to raise the track more than the cork thickness. If on the entire base it does not allow much thickness for contouring your scenery and landforms. Rigid foam is available from 1/2" to 2" and would be a better choice IMHO.
LION has used 1/4" fan fold, but not for road bed. It makes fine tunnel walls, back drops, passenger platforms, etc. A drawback of this product iw that it has little dimples in it (metric on one side and US inch on the other. Even after painting it remains visible.
Here is is seen edgewise representing cribbing on the Franklin Avenue Line.
LION thinks that it is far too soft to use as roadbed material.
LION bought a damaged package of this product at Menards at a great discount. It is handy for lots of other stuff, I have almost used it up, I may have to buy some more.
ROAR
I’ve been using fan-fold foam as a substitute for cork (and other) roadbed, carved to appropriate ballast shape. Underlayment is thinner cookie-cut plywood (5/16 mostly) supported at least every 16 inches and occasionally stiffened with steel angle iron (extremely low humidity and high temperatures equal bad results on forest products. My steel benchwork remains unaffected.) Some of mine has been in service for seven years now, with no adverse problems noticed.
The OP mentioned heavy locomotives. Unless they are large scale live steam, model locomotives don’t put anywhere near the stress on roadbed and subgrade than that applied by pushing track nails into it, assuming that the nails reach the plywood before the heads reach the ties.
Chuck (Modeling Central Japan in September, 1964)
There are others here that have use the fan fold (extruded) for roadbed w/o any problems. I use the product, but for it’s intended purpose under siding. It will support your track/ loco and then some. I can walk on even small strips w/o crushing the foam. Once calked in place and track ballasted it will be no different than any other extruded foam/ thickness.
Why use or what is the need for the added hight then add cork? the foam can be cut for roadbed alone.
Instead of cookie cutter I was thinking of going with a sheet of 1/2 plywood with track raised to give room for more variation in scenery height. Using Woodland Scenics risers for incline, was looking for a lower cost product for level areas. I was thinking .25" -.50" so as to not sacrifice too much backdrop hieght. Do they make the blue or pink foam in 1/2"? There are so many decisions to make when starting a layout that it can cause you to procrastinate and get nothing done!! Ive got a large pile if lumber, lots of ideas and NO PROGRESS in last month 