TimJ

I'm repainting a steel mtb frame and am in the process of sanding down to a good surface for primering (I'm not going to strip it with chemicals). In a few places the original clear-coat is yellowed and flaking off. It's sort of plasticy and when I sand it there's a definite difference in texture and they way it breaks up compared to when I get down to paint. My question is, am I going to have to take off the clear-coat everywhere in order to get a decent paint job?

I haven't dealt with this kind of stuff before, but I'm familiar with furniture refinishing and I know clear varnishes act differently than paint. A varnish or plasti-cote kind of thing, if you spray something over it it will often bubble up and strip off in reaction to the paint or clear coat or whatever it is (if it's a clear coat and a different brand it definitely will). will this clear coat act the same way? Or where the clear coat is still well bonded to the paint can I just get it rough and primer over it? Yes, I guess I'll find out when I'm ready to primer, but if anyone has any applicable experience I'd like to hear about it.

duane041

If the clear is that brittle, it's probably going to have to come off completely. You don't want to skip during prep. If you do, you may wind up just doing the whole thing over again. So I'd get all of that clear (and as much color as possible) off the frame.

The clear that you will use will never hit the paint that you are dealing with now. Make sure when you shoot that primer that it dries completely before you do anything else. I would let it sit for 2 days, at the least, depending on what type of primer you'll be using (if you're using spray can primer, be prepared to wait even longer).

colnagorider

Nothing descent comes out of half-ass preparation. You should know that if you have been refinishing furniture. The more you put into it, the better the outcome will be. Maybe it will work, maybe it will not. Sometimes it works, sometimes it doesn't. The best thing to do of course is to comepletrely strip it but since you said you weren't going to do that, then apply what you know from the furniture refinishing trade. TEST IN AN INCONSPICOUS AREA FIRST.