I have an old car that was painted 35 years ago in Dupont Centari. It needs a re-spray, and I would now like to spray it in single stage urethane. Would I be able to sand the old Centari down a bit and use it as a base coat? Would I need to apply a sealer coat to the old Centari?

https://www.dropbox.com/s/hpz6wz8gnqtppq3/DB%206-19-2020.jpg?dl=0

If the paint is still sound, i.e. not cracking, crazing or peeling then it can be overcoated, ideally with a sealer first and after sanding thoroughly with P800 wet or P 500 dry.

With a vehicle like that I'd consider doing it again with the Centari L400 acrylic which will give you a "period correct" finish.

Thanks kindly for the reply, NFTS.

"I'd consider doing it again with the Centari L400 acrylic which will give you a "period correct" finish."

Think so? Now I'm strictly an amateur painter, but I always felt that urethane more closely resembled the paints used back in the 1920s. However, I have been wrong once or twice before, so other opinions would be appreciated. If that's the consensus, that's what I'd better do.

I've done a ton of vintage automobiles and i'm with Chris on the A/C. the A/C is a good product as is the urethane. one thing I would do is use a sealer coat. the thing with A/C is when it was applied did they use the hardener? Centari could be used with out and some people would cheep out and not use it. it was almost as much as the color its self doubling the cost. on your finish if you were to have a sand through you MIGHT see some lifting at the edges, if the hardener wasn't used. be sure to sand down to at least 600 these single stage products shrink horribly and the black is going to magnify it. Dupont has several sealers available be sure to study up on there use.
Jay D.