Problem with PPG DP primer

I am using PPG DP primer on my plane. I have used it in the past without any problems. Several weeks ago I shot some primer on my wheel pants and it still hasn't cured. I shot some primer about a week ago on some other parts and it's nice and hard. I'm sure I must have screwed something up when mixing the first batch of primer. Maybe too much or too little hardener. I use those cups and I must have looked at the wrong line.

The question is, what do I do? Can I shoot properly mixed primer over it and expect the old primer to then cure? Or do I need to try to get it all off the wheel pants?

I'm not looking for a primer war or why I'm stupid for using mixing cups, thank you though. Just trying to solve my problem.

Cam

Take it off

I use DP primer also. It will eventually dry but I'd probably just wipe it off with a few rags and lacquer thinner. You can probably wipe it all off in a few minutes. Move on.

You might consider that the hardener is no good. My understanding is that they go bad when exposed to air. For example, a half empty container with a bunch of air and moisture inside. I'm no expert by any stretch, but I can't imagine spraying over it to be a good idea. The good news is that DP comes off pretty easily with solvent. I've used acetone and scotchbrite to remove it in the past and it was no big deal. The only issue with this would be any underlying filler that might get wrecked.

I tried just wiping it off with solvent. It's kind of half dry. It's dry to the touch but balls up when you sand it. Unfortunately I put it on very think to catch a few pin holes I might have missed. I guess I'll try scotch bright and a stronger solvent.

The hardener was brand new and I've used it sense with good luck. In fact between the time I wrote the first post and now I shot primer on my cowling and gear leg fairings, and it's dry to the touch already.

dont shoot

dp primers thick. and did you wait the induction time of 30 minutes.

cytoxin said:

dp primers thick. and did you wait the induction time of 30 minutes.

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I'm using DP402 and PPG says no induction time. I do give it about 10-15 though because it's a bit cold outside.