I've used blackboard paint directly on plaster before with ok results but I want to make one to fix to the inside of a panelled door.
I happened to catch an episode of "How it's Made" the other day on TV (Quest) and they showed a blackboard being made a metal (unspecified) surface bonded to a ply backing and then sprayed with blackboard paint.
Plywood especially from the sheds has a really crap surface finish that even a lengthy spell with a sander probably can't fix so I was thinking of a similar approach to the commercial ones shown on the tv.
Would I be better with mild steel, aluminium or something else, maybe mdf bonded to a plywood backing?
Any recommendations for blackboard paint?