I am thinking of building a portable layout to go on top of a small picnic table we inherited from my late brother. I am thinking of using extruded foam perhaps 1” thick and Kato Unitrack without ballast. Size will be roughly 2.5’ x 5’
Wondering will foam be strong enough to should I consider other materials?
1" Styrofoam may not be thick enough and can break. I´d suggest to use 4" and glue 1/8" hardboard to the underside and the sides for protection.
Btw, you can enhance the rather plasticky look of Kato Unitrack quite easily. I spray-painted the track in a dark brown color and re-ballasted it using fine N scale ballast.
I am not sure if I am going to ballast or not. This layout will be portable and ballet could flake off.
I agree that 1" would be on the weak side, but to me 4" would be overkill. I think 2" with a 1x2 frame would be plenty for your size layout. A layer of 1/4" plywood under the foam might help protect the bottom a little if you are going to move it frequently.
By the size you list it looks like you are cutting from a 4x8 sheet. Plenty of excess to attach to the top for landforms, which strengthen the main layer. I used inexpensive laytex caulk for the adhesive and have had no problems.
Good luck,
Richard
The pictures show a mini-modular layout, with each module being only about 12" by 6" - fully portable. The ballast is glued - if done properly , nothing “flakes off”.
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No need to ballast Kato Unitrack to get a good look.
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Once the surrounding scenery is in place, it will look just fine.
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-Kevin
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