Primer before powder coating?

[Dorfie]

Working on baffels and was wondering if I should prime as I go along. I am planning on powder coating and not sure if I should leave them naked or primed. Should I leave all pieces separate till after powder coating and then rivit? If no primer, should I scuff the surfaces for powder coating, or does the vendor do the prep work?
Also, which color for baffels works well. I have seen only unpainted and black. Will lighter color (eg white) make it easier to see oil and other leaks?
Thanks.
Johan

[MarkW]

I have a friend that does powder coating. They prep everything. Do not prime ahead of time.
I was told dark colors hide oil leaks and the baffles should be light.
I was told this after I painted mine a nice gloss black.

[xblueh2o]

Mark is correct. If you mean apply a paint primer, then no, don't prime.
One of the first things a shop is going to do is media blast your parts anyway to remove everything from the surface. Just like paint, the key to a good powder coat job is all in the prep. After the part is fully prepped and the powder applied it will then get baked to a temp just slightly north of 400 degrees.

[Dorfie]

What about riveting parts together prior to powder coating (as the plans call out)? Should I leave all parts disassemled until after powder coating? I quess the powder coat might not penetrate where two parts are riveted together. Does it matter (will the powder coat seal the joints)? If I leave everything disassembled till after coating, then the rivets will be unpainted once assembled. I also quess that the rivet holes will have to drilled again to remove paint in the holes?
How much thickness does the powder coat add? I was thinking to powder coat the step (RV 10). The part that slides into the fuselage is a tight fit and adding thickness will prevent sliding them back. Maybe powder coat only what sticks out of the fuselage?
Sorry for all the questions, I have never seen the process.
Thanks.
Johan

[David Paule]

Rivet, then powder-coat.

My baffles are powder-coated white. They are hard to clean but the engine area is easy to inspect. The powder-coating held up well for the first 500 hours but now there are places where the paint is cracked and worse, chipping off. Still isn't bad, though.

I haven't decided if I want to do that on the RV-3B, but I'm not nearly there yet so there's time.

Dave
RV-3B, still on wings.