Question about drying times ab work and clearcoating

[hamaf]

Hey! have a question... Let's say that I have a hood that has been basecoated black. Now, the tech sheet says(does it?) I need to clearcoat it in max. 12 hours or 1(!), how do I airbrush a super detailed mural in 12 hours? :-D

And the solution is probably to clearcoat it first then scuff and then start airbrushing the mural with let's say wicked colors, which do not have a maximum curing time before clearcoating. All good, mechanical bond into the scuffed clear and over the wicked and wicked bonds to the scuffed clear, but what If I'm using the same basecoat that has a max curing time before clear? Then I'd have mechanical bond into the scuffed clearcoat but what happens to the mural? It has dried too long. Or has it really?

And then the mural could cover almost the entire hood, there would not be mech bond between the hood and the next clearcoat, all of it would be on top of the new paint which has dried too long.

Am I dumb, what have I missed? Is this one of those things where tech sheets don't apply, because rule books generally go out the window when airbrushing is involved?

Thanks?

 

[Mr.Micron]

Never airbrush straight on to the base coat , Alway have a coat of clear over it to protect the base coat and airbrush on the clear coat , If you screw up you only have to go down to the clear coat layer and not a total repaint.

 

[hamaf]

Yes that is of course wise, but how can people airbrush with urethane if it has a max curing time before clearcoat? One would have to finish the airbush work inside that time, is that what they really do?

 

[Mr.Micron]

Most will not spray on the base coat at all , After the base and clear are finished they use an intercoat clear to get around the flash times of the paint.

 

[BrianPaints]

There are a few ways around the spray time issue, but the best is to clear, scuff and airbrush, and clear again.
You can use an intercoat clear to reactivate the urethane after airbrushing, as well, which restarts the 12 hour window.
Many do it the wrong way, and simply ignore the 12 hour window and clear over basecoats that have been sitting a few days. They'll all tell you they've never had a clear coat delaminate, but that's mostly because people just get it fixed somewhere else rather than try to get a good paint job out of a bad painter.

 

[Squishy]

All I can say is, I have used Wicked over non cleared base a couple of times. The base has been maybe a week or two old, then spent a couple of days painting before clear. I know its not the right way, however I have, some that is getting on for 4 years old and still looks as good as the day it was done, and I see another from time to time. But clearing scuffing back , painting the art, then clearing again is the way to go.

 

[hamaf]

Okay thanks! I'm not going to airbrush with urethane but was just wondering how do they do it.