Hi All,
Yes...it's me, the one who builds all those Depron models in MB magazine. I was a woodwork teacher! and love wood (but MDF is not wood, its a recycled paper product shredded to dust, mixed with a binder then rolled out into a gel like sheet and baked. Unless it has a Urea Formaldehyde binder it is not waterproof and will absorb water at a prodigious rate. According to Design and Technology H & S guidelines it is really not recommended for teaching children woodwork in schools as it is regarded as a carcinogen)
I have used Depron foam for 3 years or so, along with other foams in my several model articles, the ones that are covered in ladies tights (don't tell the wife!)...Depron is an expanded Polystyrene board and often used to build lightweight model planes. It should not be glued with pipe adhesive or any of the plastic solvent or impact type. There are glues for it including Foam Safe cyanos, Deluxe Materials Canopy or R/C modellers glue. Hobbyking do a 'Foam Glue for it which is messy, epoxy works well and some Aliphatic resins.
I have also used Foamex which is great in the thicker sizes. Depron is easily available in 2,3,4,5,6,9mm thicknesses, it has no grain pattern so parts can be cut in any direction. It is particularly good for children, no smell, no dust, easy to cut, dimensionally strong, impact resistant (up to a point) Totally water resistant, UV resistant, cheaper than plywood and Plasticard.
A lamination of 3mm Depron with an applied skin of nylon, tissue, fibreglass etc and coated in epoxy resin or Acrylic varnishes is very similar to the skins now used on lightweight full size home build aircraft, with an aluminium skin it is often used in commercial aircraft, full sized boats, some body and surfboards and many other modern products.
It is not the be all and end all of building materials, but it is quick and easy to use, where it is more appropriate, of course I would use plywood etc......Its all Horses for Courses.
Cheers............Ron.