I was shootin the crap with the local jobber that I have known a long time. He's knowledgable and sprays himself. Anyway, I was telling him that when I spray clear on a resto I spray 1 coat in the morning, 1 at noon, 1 afternoon, and one at night before I quit. He told me that I was asking for solvent pop doing that. I asked him to explain but he really couldn't. It was like asking a UAW retiree to explain his reasoning. Just cuz I guess. I told him it made sense to me that letting a lot of time between coats allows the gases to escape. He said 20 min between coats is best and then the entire 3-4 coats will cure together and are less likely to trap solvents. It seems to me that way you have 3-4 barriers to stop the gasing? Or doesn't it matter at all. I've had solvent pop once and I think it traced back to my radiant floor heat in the booth set at 90 degrees. Surface temp was over 100 degrees as the floor temp was also that warm to heat the air to 90. I think that hot of surface temp skimmed over the clear and about 3 months later it popped. That or it was just bad luck as I painted two other cars the same way and they never did it. All three were painted with dupont premier clear before I switched to SPI.