I bought one of those vintage Aurora Postage Stamp train layouts (from the 60s?). So far I removed the track and washed the whole layout to remove years of dust. The base is made out of styrofoam and I guess in the past somebody tried to "plant" trees or something else with either styrofoam melting glue or a heat gun which just basically melted parts of the layout. Those would be the holes on the left side. What would be the best way to fill those missing pieces out? If possible, I would like to somehow retain the styrofoam's softness so I can replant trees in those areas. Also, the layout has a lake in the middle of the layout which I would like to turn into a small town. I would need to fill about 1/8" or so to make the lake flush with the surrounding area. Any recommendations on what to use?
My first thought would be spackling compound, light, easy to work and to paint. That's neat that you found one of these layouts, Postage Stamp Item 4700. http://davidksmith.com/postage-stamp-trains/pst_4700.htm
In terms of keeping with the styrofoam you could use some of the spray on foam insulation you can buy in a can, but that stuff can be hard to control. But it would work to fill in the lake. You'd have to do some sanding to get your shapes back where you want them.
Woodland Scenics makes a product called Foam Putty. I’ve never used it but It’s supposed to have the same characteristics as foam. You can see it here https://woodlandscenics.woodlandscenics.com/show/item/ST1447 It might just be light weight spackle. Maybe someone here has used it and can chime in.
Spackle or drywall mud would be a lot more brittle than foam board, which itself flexes a lot more than drywall. Maybe they've come up with something that dries a little more flexible than drywall mud. Note that even drywall mud typically needs paper or mesh tape to re-enforce the mud across the joints, and is supposed to be applied in comparatively thin layers, and drying between each layer application. It would be nice if there was a more flexible, foam-like substance that was not so sticky, such that it could be tooled/shaped better during application.
Be sure to read WS' application info on their product page. While it adheres readily to styrofoam, other foam board materials should be sanded (suggested 80 grit) to ensure adhesion. It also has a shelf life. The shelf-life and adhesion recommendations may apply to drywall compound too.
I've used a DAP product called Elastopatch, which is a flexible patching conpound. It's sort of a cross between spackle and silicone. Down-side is it isn't sandable.......I used it to fill in the joints between my layout sections where I could put it in and smooth it out........but you need to get it to shape before it dries. But after it dries it IS flexible.
Thanks for all the replies. I used plaster of paris for the holes as I found that at home. For the larger lake, I am thinking of just sanding the edges and use it as is. I am not sure how level I can get using any type of material.
