DP lays down great for me with almost any of my guns.... Looks like you are needing more fiddling with your gun tip size, settings, pressure ,etc. DP is not fun to wet sand but it can be done. I'd sand that flat with 400 and this time make your DP to their recommended "sealer" consistency for another "flow coat" of the epoxy.

Thanks. How long would you suggest waiting before wet sand?

Just test it and see how it sands. If it trys to gum up give it another day or so and try it again .

As suggested, I wet sanded that DP and reshot. Turned out a lot better the second time, but probably not as good as it could be. At this point, I did notice a few little pinholes that I probably should have fixed before I reapplied the DP. No biggie. Still in the learning curve. So...I filled them.

I also got a little ahead of myself and put a big thumb print in the second coat of the DP. So. I filled the necessary spots and decided to go with the K36 high fill primer. I don't have a shot of that after I block sanded it, but it looks pretty darn good. I finally feel like I accomplished something. It's ready for base coat.




In this pic, I still don't know what's going on with these areas where the edge of the original paint are. Is there a chemical reaction going on with the primer and the metallic in the base coat? Call me stupid...but I put filler on it, feathered it out, and primed over it. Looks like it finally went away. I'm just hoping this doesn't continue to rise to the surface or cause an adhesion problem. I think I've learned my lesson and will take the next fairing down to plastic over the entire surface. (Did I tell you that I have 3, maybe 4 of these to do?)

While I was priming the outter fairing with the K36, I called my buddy and had him bring me the inner fairing/dash piece. He also wants that painted.

I spoke with a local painter and he said that shooting it with an adhesion promoter and then prime/paint would work fine. So...that's what I did. Adhesion promoter and 4 coats of the K36.

It SEEMS as though the primer is stuck like a champ. Does anyone want to chime in here with a horror story about how this will fail in a short amount of time?

K36 is pretty good stuff. No real horror stories for you but I just prefer to have that epoxy "barrier" when working over the plastics like this. May never be a problem for you, could "show" moderately with some shrinkage, or an extraordinarily hot day could cause some problems. I know guys that do it both ways.... with and without epoxy.

Darrel....forgive my ignorance. Can you tell me why epoxy is important to you, and why it's often called a "barrier"? Is there potential chemical migration from the plastic that causes adhesion issues down the road for non-epoxy paint?

Can you address that funky reaction from what I assume is the metallic in the original base coat? Would you agree that going to bare plastic is the best course in the future, or is this just something I can deal with like I did on this particular fairing...use a high-build primer to encapsulate and bury it? I'm kinda certain the answer is not the latter. I worry about this being the weakest link in the chain.

thx

You are not being ignorant here.... There is controversy within autobody circles on these issues and procedures with many plastics. Metals and even fiberglas are fairly straightforward in steps outlined in product sheets. Various plastics....ehhh... not as much. I refer to epoxy as a barrier in much the same way we refer to shellac as a barrier in wood finishing systems. It is a material that can stop hotter solvents from getting down to something that can react. And, with the addition of summer sun exposure I have seen some plastic react by trying to "off gas." As for your reaction there.... yeah, I'd agree with you in some kind of reaction with the old base probably because the epoxy had more reducer in it ... Epoxies (especially when reduced) can react with solvent sensitive coatings.
Personally I don't like to work with raw plastics as existing factory applied coatings provide an excellent base for building the new paint package.... can you run into spot problems, well, sure, but you can deal with them as they come. And, obviously you would have had no problems if the full strength epoxy had laid down right first.

Thanks again, sir.

The hardest part, for sure, has been the voodoo of painting on plastic...as you mentioned, there are opinions galore on the accepted process. It's been very hard to settle on a process given my lack of experience. And seriously...if plastic is even mentioned, ABS is generally not. So...I usually feel like I'm doing something wrong.

Yep, ABS is a real kicker when it comes to plastic.... Even the pros that manufacture with it can have problems. I worked my way through college in the tool and die section of a large plastics extrusion company. We had just a few ABS machines in the plant and they required top operators to constantly monitor flow and temp. Even with that now and then a heated extrusion die would run "wild" past it's temp. rating and start to burn or "gas" the plastic. That gas was toxic and we would have to evacuate the plant everytime it happened. None of the other plastics were that hard to control.