Many thanks Spurno - yes on a quick search it looks easily available and also at reasonable prices compared to Hornby etc equivalent.
Ray

Hi Chris,

Before you go bang busters and lay yards of closed cell foam underlay, beg, borrow or buy a small quantity and test it with the adhesive you are going to use. I had an issue with some closed cell foam that would not adhere properly to untreated cork or ply using regular white glue (PVA). Being closed it is not porous, and it is additionally hydrophobic (sheds water). The PVA just formed a skin on it. I ended up using the old favorite, cork-based track underlay, which is a cork-rubber mix and is quite flexible. And which glues down fine using PVA, and goes around corners quite happily. I know a few modelers who have used W/S closed cell foam underlay, most were not that happy with it.

I suspect a solvent based adhesive would work, or one with a reasonably high VOC content.

Nigel

Wood glue would probably do the job. even if it doesn't soak in. It dries fairly hard. Hot glue might also work, as might caulk.

Now, if I were a Model Railroader magazine staffer I would tell you that Homasote is the only roadbed worth using, but I'm not and it isn't.

Hi Brendan,

If PVA doesn't stick, chances are that regular wood glue won't (it's PVA-based as well). Homasote - paper maché, basically cellulose fibers. Beloved of hand-laid track aficionado's as the spikes go in without bending. Needs 12-16" centers or open-frame construction.

I keep it simple, 3mm or 6mm Baltic ply module top (depends what's around) with cork track bed. PVA for gluing down (I'm not a fan of acrylic calk, silicon is OK, marine version, sticks well and gives a bit of flexibility)). Tin cans filled with concrete as weights. Regular HO for main lines, N for spurs, etc., sheet for yards. Homasote track bed strips are available for those so inclined. Like you I'm not.

Nigel