Ive been reading alot of threads on here about the above materials, am i right in saying theres no right material to use for subroadbed and roadbed?
I was going to use 1/2" ply (cookie cutter, on risers) topped with 1/2" styrofoam followed by woodland scenics roadbed. Then i read about the styrofoam being stable in all temps while the ply will expand and contract so shearing the bond between the two!
At the moment i may just use 3/4 ply subroadbed with WS roadbed and put up with abit of noise.
I wouldnt use foam on its own as i cant see it being strong enough long term, also fixing it to cleats and risers would be less than ideal surely?
Homasote does not seem to be available here unless its called something else.
After all these threads, im still none the wiser. Dont realy want to make a mistake selecting the wrong material, been there and done that!
Gary, On my HO layout I used 1/2’’ plywood and glued cork roadbed directly to the wood, and I do not have a noise problem at all. The plywood structure is strudy enough for me to get on it and work if I have to. Others will surely give you some different ideas. Mike
I am planning on expanding some day and I am looking into the same way I am going with the exception I may use the foam for the mountains and hills. I think it would be easier than plaster cloth and newspaper wads. Mike
WS roadbed on plywood on risers on L-girder is my choice. Sheets of foam are good for a flat layout or one that uses WS foam inclines(good but expensive). I use stacked foam for mountains and valleys because it is cheap, easy, lightweight(especially for removible sections) and I can carve my rock formations directly in the foam.
Homosote was the choice years ago, and has no bad side other than it is one more step. For a 4x8 flat layout, I would choose foam over homosote.
Homasote appears to have 2 specific qualities that make it the best roadbed when those 2 qualities are a priority.
it is about the best roadbed for spiking rail or track. Homasote is soft enough not to bend spikes, but holds them very well. Those who spike handlaid track love Homasote.
it is probably the most sound absorbent of the commonly used roadbed materials. This might be important to bring out the sound in your sound-equipped model locomotives. But I should also note that if the ballast glue reaches from the track to the plywood or foam under the Homasote, the sound absorption has been bypassed, particularly if white glue or similar is used.
If neither of these qualites are at the top of your list, other roadbed materials are cheaper, easier to find, and less trouble to cut and fit.
Gluing plywood and foam together will further reduce the expansion/contraction of the plywood. I’ve never seen such a glue joint shear in real world use.
My previous layouts were Homasote on 1/2" plywood. On the next layout, I’m going to try 1/4" plywood under 1.5" foam, normally supported on risers spaced 16". Roadbed will be Homasote glued to the foam. The reason for the plywood/foam sandwich subroadbed is to get smooth vertical grade transitions (by bending with risers) without the weight of 1/2" ply. I am also counting on the foam to further stabilize both the plywood and Homasote. For scenery, I am going to try “foam shell” using thin foam sheets sloped between tracks rather than stacking thicker foam horizontally. My goal in doing this is to achieve the hollow underneath for wiring, switch machines, and uncoupling ramps, while at the same time presrving the tree planting and light weight of foam.