Working with foam board

[Anonymous]

I actually have some real experience with foam board. The pink stuff is sold by Home Depot and
the blue stuff by Lowes (I think it's a marketing
thing). How to glue it is the key. I tried everything until I discovered tubed caulk sold at
Home Depot - make sure you get or ask for the stuff labeled "For Projects and FoamBoard". Nothing else works well - Elmers will not dry and
glue guns at high temp will melt the foam and at
low temp take too long to work with. After you have your mountain or other structure made you can
fill in cracks and crevices with spray can foam
also sold at Home Depot - it works great to adhere
to the foam since it is essentially foam itself but it drys smooth so remember to keep disturbing it so it drys irregularly if you want a textured surface. Woodland scenics sells cutting tools but they're wimpy and the wire has to be replaced relatively often. Go to a Dept. 56 retailer and ask for their foam board cutter - it uses a solid wire and works much better. Krylon will not work on foam board because the organic fumes melt the foam, layer your structure with typical plaster sheet and use woodland scenics water based colors.
Finally buy the one inch thick foam board sold in 15ft (yes) lengths at Home Depot and layer cut sheets irregularly for mountains or glue together box like structures for tunnels and put irregularly shaped sheets around them for mountains- layer the sheets together using the caulk and glue together sides of tunnels with a
hot glue gun - the latter for best strength, keeping in mind my previous statement. Outer edges of walls are best to use a glue gun, outer edges will dry (the glue that is) - for sheet to sheet glueing you need to use the caulk because only it is designed to dry with no air exposure.
email me at [e-mail] if this is not clear.

[Anonymous]

My layout uses a lot of 1" foam board, the thinner sections need some support, 1/4" plywood is sufficient, thicker foam (1"+) may not. a 30x12 section would be a good candidate for a sheet of 1/4" ply or a few 1x2 stringers.

I glue sections together with elmer's carpenters' glue (aliphatic/yellow).

use latex paints, i bought a gallon of mis-mixed paint at Home Depot many years ago, it's a "dirt" color and i've still got lots left.

Hot knives work well, but i've used a stanley "sur-form" rasp mostly. messy but effective.

[raysaron]

We used 2" pink foam board on a 4' x 6' (N scale)
layout at our club. We glued it to a 2 x 2 wood frame (with one central cross piece) with Liquid Nails. There is a special formula for use on foam that I think is called Project Adhesive. We used the same adhesive to glue layers together. I weathered the track with spray Rail Brown and we painted the scenery with the cheapest latex paint we could find.

Hope that helps.

Ray

[Anonymous]

Does anyone have experience working with this and any recommendations? I have heard to use the pink or blue board and I have some hot wire cutting tools I bought last year but have never used them. They heat up and then you can cut the foam board.

Can you use acrylic paints, gesso, and matte medium on foam board? These all seem to be water base but will they ruin the foam board.

Aslo, what type spray paints can be used on foam board? I have some Krylon spray paint and the can says you can use it on plastics and rubber and most materials.

What do you use to glue foam board pieces together?

Finally, do you have to use support under foam board if the largest unsupported area will be about 30 by 12 inches?

Thank you for you help. All help and recommendations would be appreciated.