One thing I learned years back is make sure all your paint products are same brand and compatible with each other. I'm a little confused though, why would putting a urethane paint make lacquer primer lift? The other way around, putting lacquer on top of urethane might make it lift. Again I'm no expert, and have only sprayed 4 cars, 3 motorcycles. I used to use dupont lacquer primer, I think it was called 131, it's been a lot of years back. I sprayed single stage centari enamel or 2 stage base coat/ clear on top, never had a problem. Maybe your brand primer needs lacquer top coat! My two cents worth, Moose.
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Lacquer primer (and topcoats) can lift because they can be returned to a wet solution by applying a heavy topcoat of most any solvent based system. The solvents in the new product essentially rewet the primer. Modern solvents can't be used to reduce a lacquer based product because of incompatibility, but can cause the lacquer system to become a wet solution.
If this doesn't happen to you fairly quick, from the first few seconds to about five minutes, then it probably won't happen. Mind you, if consecutive layers are laid on too wet, or too quickly, the solvents still can soak down to the primer layer and cause lifting.
They don't always lift, but can relatively easy.
Lacquer on top of a
eurethane can cause lifting because of the caustic nature of what it is reduced with (lacquer thinner).
Once you sand a
eurethane surface, you open the paint up to allow adhesion for what you are topping it with. If it is lacquer, it gets soaked with the thinner and will usually cause the underlying base to return to solution, breaking the bond of it from the surface and swell because of the additional solvents present. This causes the clear coat to float and "wrinkle" giving you that lifted look.
When we used to shoot lacquer systems back in the late seventies and into the early eighties, lifting was a general issue that you had to learn to work with when repairing a previous paint job. It didn't seem difficult at the time, but that was just part of painting then.
So, if you use a lacquer product now, such as rattle can primer, it's best to start coverage with a couple fairly light coats prior to heavier coverage coats. Allow those first coats a little extra time to dry prior to the heavier coats as well. That provides kind of a "barrier" coat.
I hope this makes sense. I could probably explain this to you in about one minute talking to you, but typing it out seems to take forever. If you want a more detailed explanation, pm me.
BTW, lifting can occur with
eurethane products as well. Somewhat the same principal as listed above. It's just less likely since modern reducers aren't as aggressive in causing the underlying layers to return to solution.