Painting over stonechip

[Matt S]

Hi guys, I've done a search but couldn't really find a definitive answer... How do you prep stonechip to overpaint? It's proper overpaintable 3m stuff, not the black underbody schutz, but I wouldn't have thought I could scuff it prior to painting due to the texture! Do I put the following coats on before its fully dried? Do I need to use a primer, or can I go straight over with the base coat in thin layers? If I need primer, 2 pack high build the correct stuff? Any help is much appreciated

Matt

 

[marlinspike]

I think you just put the top coat over the stonechip, from what I have read previously. You need to make sure the stonechip has fully dried though or you may get a reaction. It was Rocket man who had some issues with stonechip and top coat reacting and ended up stripping off the stonechip.

You can use primer over stonechip but not sure why you would want to other than as a bar coat.

 

[Rocketman]

Yeah I had massive problems with the hammerite stuff - it's quite soft permanently and takes a considerable amount of time to fully realise its solvents to cure. Changed over to decent Upol stuff which is much better - though if you still hit it with enough solvent it can crow foot - so some care needs to be taken with 1k top coat products.

The idea of primer on top of the stonechip is so you can get a better gloss using less paint. I have the data sheets somewhere for the upol stuff. You don't have to use a primer but they say to get a better gloss it's easier to achieve with primer.

TBH I don't know how the 3M stuff compares to Upol therefore I don't know if the 3M stuff benefits from a primer.

 

[steveo3002]

pretty much always painted over it at the bodyshop , would let it airdry for maybe an hour so its mostly gone off then paint

if you wanted to smooth it over a bit you can high build and lightly sand it