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New Member
I just recently got back in the hobby after 10yrs in making the layout i need to confirm from anyone is using OSB instead of ply o.k.?


OSB may be more susceptible to humidity than plywood.

It is also heavier than plywood and a bit more difficult to cut (it dulls blades quicker).

Hope this helps.

Darrell, quiet...for now


Active Member
thats what i had laying around (lots of it) so that's what i used for my top. one note though, i would not lay rail or roadbed directly on that - used sheet of extruded foam .


N Scale with Stone Tools
Tankist, why not? Is it dimensionally unstable? (Just wondering, Home Despot has it for about five bucks a sheet here.)


Active Member
well as far as stability it is ok in my attached but unheated garage for year and a half now. main reason i put foam on top is to be able to carve depressions in ladnscape and such.


I used foam on my layout too and it is nice to be able to dig down into it if you need to. I also found that the leftover stuff was great for stacking and then carving the mountain shape of your dreams. Kinda makes a mess but it looks pretty good. Trees are real easy to plant in the foam too.

The only problem I had with my foam mountain was the mouse who decided to live in it. Guess the insulation kept him warm.


Active Member
Yes, here is another vote for 2" foam on top of the plywood. Make sure you get the builders extruded foam. It's either blue or pink, depending on where you live. Don't get the white stuff! it crumbles.

I also used pieces of the foam stocked up to build hills, mountains. You can use it for anything really. and for carving out rivers and creeks.

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