Greetings,

I have a few patterns that are made from either plastic or glass. I wanted to know if the above gelcoat systems would effectively work on the materials listed. Are there plastics that are incompatible with either of the gelcoat systems?
Thanks.

It depends on the plastic.  Uni-Mould uses styrene based plastics so anything styrene based can be dissolved or surface attacked.  eg polystyrene.   The epoxy is much more inert and does not effect virtually any plastics. 

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant