Sorry for delay Bob, SWMBO dragged me out by the tinsels, (Bl---y Christmas again, Hum babag) You can get this foam from a local construction site, scrap bits or from Sheffield Insulations in sheets, it was mentioned on a thread before, when Holmsey wanted a block for something. You can cut W--g cores out of it , use it to make a "Plug" for a glass hull, but I've also used it in place of block balsa. Can be cut with a knife, sawblade, hot-wire or soldering iron at a pinch, can be sanded and plated with paper or epoxy resin. S.I. are a national firm, my lumps of foam were a sheet with a damaged corner, cost "A DRINK"
Know what I mean
Yes it glues with PVA or Aliphatic or araldite but keep glue clear of sanding edges.You could also make deckhouses with it.