Polyester and Epoxy are compatible.

Polyester and Urethanes are for a very short time period. If the poly is under the urethane it will off gas and eventually create bubbles in the urethane and ruin your plug. I ruined many, many plugs this way before some one mentioned the compatibility issues.

When building plugs Polyester primer is all you need. It can be polished to a mirror. Really is no reason to use anything else.

For bonding always use epoxy and under 100 grit sand paper for prep. You’re relying on a mechanical bond if youre bonding post cure. Bigger scratches for the epoxy to bite into, the better.

Jason

Thanks for the suggestion - Is there a document anyone knows of which ‘lists’ compatibility of finishes with polyester and epoxy?

Are polyester abs epoxy compatible? So can I bond polyester glassfibre parts into a CF part or do I use epoxy and glassfibre for that or should I only add epoxy CF to a CF part?

Bit confused about the compatibility rules!!

Why not use a Polyester primer like Duratec, sand it to 1000 grit finish, then polish with Aquabuff to a shine?

Jason

I am using a MDF mould buck which I need to 'smooth' with primer and top coat of paint - I propose to use a nitro-acrylic paint - will that work with a gel coat and polyester resin which will be used to make the mould?

Thanks