I am stumped. No pun as to bases though. The problem I have encoutered is plaster bases. I have tried base coating plaster diorama bases with arcrylics and primer which have slowly disolved the plaster surface. I assume that since plaster is porous it asborbs liquid based acrylic and have been suprised that primer has disolved plaster. I would prefer to retain the sharp crisp surface detail that comes in diroama bases that are commonly found in ROYAL and CUSTOM DIORAMICS.These products appear as highly detailed with surface texture that I find soon degrades with acrylic and primer. I have encountered no such problems with resin bases because the surface is not porous. I am open to suggestions, what medium can be used to keep the surface detail sharp and highly textured.

Roj

Gday Roger
I'm not too au fait with the nuances of what melts/reacts with what, but for bases I use a basic grey primer from our Home Depot 'equivalent'... Have you explored automotive primer rattle cans? I'd give them a shot...
Just a thought
Cheers
Brad

I've not had much experience myself put how about painting a thin coat of PVA glue thinned down with water? This would then act as a sealer for the then ensuing primer and paint shouldn't "eat" into the plaster. This is what I did on real plaster walls of my room before i painted it.

Allen has it. Make up a thin solution of white glue or PVA in water and spray or brush it all over the surface This prevents your paint being 'soaked' up.

Vinnie

Thanks for the advice. I will try this.

Roger

Would also agree with this. Ive done this to several plaster pieces .... both bought and self-cast/scribed .... and it never caused any problems.
Another big advantage it has, it actually makes detail and surfaces harder, and less likely to chip in awkward places showing the inner white colour.