Hi,
thanks for all your replies!
I think it's got something to do with the spraything I used to put the color on.
(this CO2 filled spraygun was getting freezing cold after a shot while) I also think the pressure was lower than the 2 bar you mentioned.
Anyway, I sand it down again and start whole over again.
Today I bought a custommade spraycan with H3 color (imperial blue 1992 etc) so should work out fine now.
I'll keep you updated !
Best regards,
Martein