Has anyone used etch primer, I am wondering how real the problem with paint-lift is at the edge of bare-metal and paint?

Is it just a case of try it, if it lifts get the sand-paper out?

Or is it likely to occur and is it best to avoid the edges?

Any other recommends for minor surface rust areas?

Etch primer is used on aluminium, etc. Have you tried zinc primer. If you treat any surface rust and spray it over, it'll be fine. I treat surface rust with sandpaper, if it's pitted with an angle grinder (and use knifing putty).

i have etch primer its very runny however it premotes adesion, however its really more for had to stick to areas, carbon fibre plastic etc

id just use a cellulose primer if its for your car removing all rust etc.

The advantage of etch-primer is that it chemically changes any remaining rust (only a very thin layer is required), zinc-phosphate primer is just an adhesive unlike the zinc paint we used to be able to get.


Like to sand out as much rust as possible, but there is always a chance of the odd speck re-growing.

I used zinc primer on my subframe after removing all of the rust, it's really 'tacky' in that you can't really brush it and dries in about 2 minutes (even in this weather). I'm spraying over the top either black or white.