Primer tips, please

[Mark Wilson]

Finally on to the painting stage after five years of rebuilding my Traveller! I've etch primed the bare metal, sprayed 4 coats of high build primer and applied a small amount of stopper to hide slight ripples which I hadn't seen when filling and sanding my curved roof repairs. While block sanding this area I've gone slightly too far and exposed the bare metal in a couple of 50p size spots. This didn't surprise or worry me, I'm more concerned about getting as good a final finish as I can, but can I ask your advice on etch priming these small patches. Rather than spend an hour setting up and subsequently cleaning the spray gun I've bought a rattle can of 1k etch and intend to patch prime with it, followed by further patches of rattle can high build. I'll then move on to block sanding with a guide coat and further full coats of high build if necessary. The question is how careful do I need to be with the etch - can it overlap the high build or do I need to mask carefully around the bare patches?

I've also got a beautiful smooth finish on the high build with 400 wet and dry. This doesn't seem to provide a very good key for the top coats - should I scuff it, and if so with what grade of paper?

Mark

[Redmoggy]

If you mask those areas before you etch them you will end up with raised edges that will require even more work. Puff a couple of light coats with your can and unless you paint wet on wet then remember to key before adding your high build.

I've never used 400 to prep for top coat but I think this would be a little course for cellulose. I always finish sand with 800 grit used very soapy and wet before colour.

Rod

[Big Jim]

I used 500 grit before top coat cellulose as recommended by the paint supplier . I found it easier to control doing it by hand than with a sander .

[Mark Wilson]

Thanks both. I found that the acid etch seemed to react with the stopper, so I've stripped that area back and will return to it when I've more time. (My priority is to use this warm weather to get paint on the shell so I've a rolling chassis to work on over winter). I did decide to use 800 grit and where it's gone well it looks good. Just going out to deal with a few runs etc and get another couple of coats on.

Mark