Hi All. A quick question regarding how to use foam. Is foam used as the primary base for a layout attached to the frame work instead of using plywood?
Thank you for your reponse.
It could be if it is either supported or thick enough to keep its shape. Essentially, the 1" stuff is a bit thin, and would need strapping below it at 15" centres…overkill, but safe. If you can get 2" stuff, it is fine on its own as a slab. However, you should frame it with 3/8" ply in a box around the permiter, and then make legs, braced, attached to the ply. Personally, I would put at least one joist under a 4X8’ slab of 2" foam, but the guys who use it swear that it is quite rigid.
In my case, I built a fortress using 5/8" GIS ply and 1" foam glued to it with PL 300. It was a waste of money, frankly, but I didn’t know any better, and had never built a large table-type layout. I didn’t want to it to fail.
I hope you know to use extruded foam,and not the white beaded kind, the kind cheap picnic coolers are made of.
Foam can be used in many ways.
It can be the primary layout surface. 2" foam will support itself if supported every 24" or so. My current layout is built this way.
It can also just be for scenery, My previous two layouts had plywood/homasote subroadbed, and I used the foam to fill inbetween the open grid benchwork and the subroadbed.
Nick
Thanks Guys.
Nick I also already have 3/8ply and homasote which is seperated at the present moment. I thought about using the foam inbetween the open grids but wasn’t sure. That is what I will most likely due being my framework is all ready done. Thanks again.
Rob
I stack the foam and am carving the rock work directly in the foam. I then paint and scenic. In some cases I paint a coat of drywall seam cement on the foam to give a different texture. I stick some together with low temp hot melt glue and some with latex caulk or liguid nails. It all works depending on what you like, but you won’t know that until you experment some.
rob_c65,
You can use it either way. On my 4 x 8’ layout, I have 1 x 3s framed around 1-1/2" extruded foam insulation and supported underneath with 1 x 3s to bring it level with the top. It makes for a nice light but rigid table top. You can see what it looks like in the link at the bottom of my post.
However, if I were to do it again, I would place and glue down the foam on top of some 3/8" or 1/2" plywood over some open benchwork, so that the foam goes all the way to the edge of the layout. Curently, with the 1 x 3s framing the edge of the foam, this prevents a foam-to-foam transition, if I should decide to extend the layout any longer - if that makes sense.
Tom
http://www.forman.co.nz/datasheets/ds_068_dow_styrofoam.pdf
Is this what I’m looking for in New Zealand?
might give it a go if it’s cheap enough.
Ken.
That is the stuff. It also comes in pink sometimes, same stuff. I have picked up enough from building site dumpsters to do most on my layout. In Minnesota they use it on the outside of foundations. When I see a building site I watch for that step and then ask the forman if I can have the waste. Many will say yes. I also found about 5 sheets along side the hignway one night, blew off a truck I guess. Some was broken, but for scenery you only need small pieces.
It sure appears to be. On the web page, they are calling the styrofoam “extruded polystyrene”. The description sounds like the extruded foam insulation.
Ken, I don’t know how much this stuff runs in New Zealand. Here in Ohio, a 1-1/2" thick piece of 4 x 8’ EFI runs about $20; 2", about $25. I really like it. It’s both smooth, uniform in shape, and won’t react to either temperature or humidity.
Tom
The stuff is easy to score, to break, to cut, and to shape with a wire brush. Be sure to keep every little shard; you never know when you might need a little shim here or there, maybe under a kinked section of track.
Below is an early pic of my layout showing, at the near edge, how it looks glued onto 5/8" ply.
I did like Selector 'cause I didn’t know any better either. Mine is 2 inch glued to 5/8 plywood.
The entire RiverDance ensemble could get on that sucker and boogie up a storm!
JaRRell