For you painting pros, it's time for me to revisit the subject I brought up a year ago in this thread (my, how time flies).
I've come to have some level of confidence in the less expensive acrylic urethanes discussed in last year's thread. But, given the fact that I'm still a rank amateur painter, I'm contemplating a mix of vinyl & paint, with urethane on the hard-to-wrap stuff; primarily the fiberglass bits like the wheel pants, but also areas like the trailing edges of the wings (in the 'C' of the rear spar flanges) and possibly the belly.
Now to my question. Has anyone sprayed acrylic urethane over self etching primer? Reason for asking: I primed the interior with NAPA 7220 self etch as I was building, and a friend who's a pro came and sprayed the finish coat, using PPG Concept DCC (acrylic urethane). It has been nearly indestructible for about a decade (literally) of me climbing around in the fuselage, installing systems. But reading through the various mfgrs' instruction docs, they say that the acid in self etch primers can affect epoxy primers, so the self-etch should be covered with *urethane* primer before top coating with urethane. Ignoring for the moment the question of why the acid doesn't affect the urethane, they also seem to say that if you prime with epoxy, you should still go over it with urethane primer before shooting urethane topcoat.
Given the good results of urethane topcoat over self-etch I've seen on my project, I'm having a hard time squaring this circle. What say you?
I've come to have some level of confidence in the less expensive acrylic urethanes discussed in last year's thread. But, given the fact that I'm still a rank amateur painter, I'm contemplating a mix of vinyl & paint, with urethane on the hard-to-wrap stuff; primarily the fiberglass bits like the wheel pants, but also areas like the trailing edges of the wings (in the 'C' of the rear spar flanges) and possibly the belly.
Now to my question. Has anyone sprayed acrylic urethane over self etching primer? Reason for asking: I primed the interior with NAPA 7220 self etch as I was building, and a friend who's a pro came and sprayed the finish coat, using PPG Concept DCC (acrylic urethane). It has been nearly indestructible for about a decade (literally) of me climbing around in the fuselage, installing systems. But reading through the various mfgrs' instruction docs, they say that the acid in self etch primers can affect epoxy primers, so the self-etch should be covered with *urethane* primer before top coating with urethane. Ignoring for the moment the question of why the acid doesn't affect the urethane, they also seem to say that if you prime with epoxy, you should still go over it with urethane primer before shooting urethane topcoat.
Given the good results of urethane topcoat over self-etch I've seen on my project, I'm having a hard time squaring this circle. What say you?
