Hi Nurseman. The general rule is that each paint manufacturer has their own line of products which are not to be mixed and matched. I have personally used epoxy primer with other brand topcoats with good results, but you always take a risk because individual companies spend a lot of money refining the chemistry of their own products with their own
I don't know who would have lead you to believe that you could put resin over a primer. Could be the MEKP eating into the primer? But hey, things happen
Once you primer, you're done. You're in the automotive world.
Ideally, you would do all of your rough blocking and bodywork first on the hull. Fill and fair with SM fairing compound and epoxy resin which I feel adheres a heck of a lot better to the old gelcoat after the fact, than poly resin. The fairing compound completely solidifies the hull where as high build primers and body fillers may chip crack or peel on a pounding hull. It's like a huge paint layer, that does not become part of the hull like epoxy. Doing this step first, saves a lot of the more expensive primer from being sanded off and onto the floor.
Currently existing gelcoat is the best high build primer while doing the initial block sanding I've found.
After the boat is pretty close to perfect you have a couple of choices...
- Shoot a high build primer then block using a guide coat, shoot again, block sand, etc., shoot as a sealer(reduced) then paint(kind of where you are now).
Or
- epoxy prime, use spot glaze on any minor imperfections during the recoat window(pinholes in bodywork,etc.), then shoot epoxy primer as a sealer, then shoot the color.
Bondo absorbs moisture. This is why we bondo over epoxy primer instead of bare metal because the heat of the body filler cure can trap moisture between the bondo and the metal.
At this point my suggestion would be, to use a marine brand filler (because your paint will crack or chip eventually in the future, even above the water line) and make sure it is compatible with your current primer. Compatibility is key. I get eye rolls for using expensive paint but the steps are clear and I use a heck of a lot less paint and it's a whole lot less work.
Hopefully that all came out good spirited. Love your work Nurseman and I'm a big fan!
