paint
 

Hi all
When painting grp panels should a plastic primer be used or would a standard primer be ok thanks in advance

You need to key the surface by removing the shine from it, use some thing like 'scotch bright' untill the surface is dull all over. I then spray on a light coat of etch primer so it bites in to the GRP then a coat of high build primer, 800 grit wet and dry to flatten,pannel wipe to clean and then start with the colour coats.

I thought etch primer bites into metals by virtue of being acidic or otherwise reactive with iron before drying. That would not affect polyester at all.

I think the acid in etch primer melts the GRP slightly which helps bonding.

I just painted my cycle wings using Phil's method and halfords rattle cans.
They came out pretty good considering I did them!