Best adhesive for attaching foam terrain to wood base?
grass mat to foam?
Thanks.
Sid
To attach foam to wood and foam to foam I use acrylic latex adhesive available at home improvement centers. I generally purchase it in the caulking tube size. It works well and does not attack the foam. I can’t help with the grass mat question because I don’t use them.
Tom
I just use PVA glue, and if the foam is layered
Bamboo skewers are glued into the foam to hold the layers in place.
regards John
No such thing as “best” in this hobby. You will get 100 answers, and they will all be right.
My personal preference is either yellow carpenter’s glue or latex caulk. For impermeable materials like foam, lay it in an “S” pattern so that no area of adhesive is completely enclosed by another (as in concentric rings). Otherwise, the adhesive on the inside will never cure.
Thanks. Really helpful. Never thought of the S pattern.
Sid
I use DAP latex caulk. FYI Elmer’s white glue will NEVER dry under foam.
The line of caulking should always have gaps to allow air to penetrate (thus the caulk to dry) which is why the S-pattern and concentric rings was suggested.
I beg to differ, we used Elmers White glue to laminate 2 4x8 sheets of 1" foam in our club. Since we only met once a month for work sessions, it was dry by our next meet. I would never use this method for my own layout - not for full sheets of foam, but I would consider it for attaching foam to unsealed wood, since the wood will eventually allow the moisture to escape and the glue to cure.
I tried hot glue for attaching foam-rubber once. Works OK if attaching to wood, but not so much another piece of foam-rubber, the heat can’t easily dissipate for the glue to cool. I expect the same for foam.
Brad
Right. Water based adhesives do take a while to cure under foam (carpenters glue is about 72 hours vs. about 2 under ordinary circumstances – but since it’s got good initial tack, it works fine for holding foam). But they do cure eventually.
BTW, I was NOT recommending concentric circles, as that does enclose the inner circles, which don’t cure.
Low-Temp hot glue works very well up to about 1/4 sheet of foam, you make blobs instead of beads. Beads will cool too fast Any more than a quarter sheet of foam and the first blobs will have cooled off and hardened before you can get the two pieces together. But for smaller pieces it works great.
I have always used regular Liquid Nails, the trick is to apply the beads (1/4" beads), then press the two parts together making sure there is good contact everywhere, then pull them apart and let air get to the glue to let it tack up for a minute or two, then press the two parts together for the permanent bond. There won’t be any melting of the foam with this method.
The strongest method is to use spray foam as the adhesive, you do have to “clamp” the layers together, I use 3" sheetrock screws and skewers, you can remove them later if they’re going to interfere with anything. You can use the screws with any of the methods described, that alows you to keep adding more foam without having to wait for each piece to dry.
Why use blue/pink foam board with a ‘grass mat’? If using a rollout grass mat, save money and glue it to plywood. Save the money you would spend on blue/pink foam board and buy some books on model railroading.
I used it once to glue two pieces of blue foam. MONTHS later it was still wet when I tore it out and did it over.
Why use blue/pink foam board with a ‘grass mat’? If using a rollout grass mat, save money and glue it to plywood. Save the money you would spend on blue/pink foam board and buy some books on model railroading.
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The foam can be carved into valleys or built up into hills prior to attaching the mat. The results are more like gently rolling terrain and less skating-rink-like than those gotten from plywood.
I seem to recall that when we did this, we peeled off the thin layer of plastic on the foam, presumably a vapor barrier. Perhaps that made a difference?
Brad