One thing I forgot! My body man sprayed a chip guard coating on the leading edge of my flares, plus the entire length of the lower body and rocker panel prior to painting my car. This is the only way to prevent rock chips. Metal, steel, fiberglass, etc. will not stop chips in the paint. None of these these materials is resilient enough to help the paint absorb hits from small rocks. Only rock guard under the paint will absorb the rocks and keep the paint from chipping.
The rock guard does leave a less glossy finish, so it shouldn't be run way up the sides. Mine stops at that first lower body line, except for the leading egde of the flares, where it goes nearly all the way up.

 

Yeah, that really is the best way to go. I'll have to look into doing that when I go to paint my car. Do you know exactly what the stuff is called? Or is it just called "rock guard"?

And I was more specifically talking about the fiberglass chipping. Its unlikely if its done right but it is possible. And on my Camaro, they made the flares by welding a piece of sheet metal on the inside of the fender well and then welding a rolled piece of metal to that and the fender to fit the curve. Then they took fiberglass or bondo (or more likely both) and filled the gap in to make it smooth. Problem is that they made it too thick and it has cracked and begun falling off in chunks. (See Attachments)

Lucky for me I have a good body guy and I'm going to have him re-do the flares. We'll eliminate the rust and replace whatever needs to be replaced, and then probably just form sheet metal to cover the top and weld it in, then grind it down to smooth it out and make the contour flow seamlessly.

 

Yes It's called rock guard, but you can also use bedliner to do the same thing under the paint. The bedliner doesn't lay down quite as smooth, and needs to be lightly sanded before paint. He said he lightly sanded the rock guard also on the rocker panels so it would be even smoother than it came out of the gun.
I sure see what you mean on your flares. The finished shape looks good, but whoever did the work did it all wrong! The whole filled area is way too thick, and from what I can tell it's all bondo. Bondo allowed the road salts to get under the paint and rust them from the inside out.
Whatever you end up doing, be sure to coat the inside of the flares and wheelwells with bedliner to seal them from the salts on the roads. Fiberglass wont be affected by salts, but steel will, and if there's any seams or pores the bedliner will seal them all from future rusting. You can buy it at auto parts stores in spray cans.

 

Actually its only rusted because the bondo/paint cracked and allowed water in from the car sitting outside. The car is a California car so I know its not rusted too bad...its mostly just surface rust with the exception of the rear flares, but the metal is thicker so it might actually be alright. And I'm in Cali too, so I dont have to worry about road salt or really even snow for that matter

 

That's good. Didn't know your location. We're lucky out West that they don't salt the roads, so cars last longer. Yea, bondo put on too thick will crack, and it doesn't take long. Once it does the result is the same as road salts. Regardless of salts or not, I'd still do the bedliner inside the wheelwells. I did mine, just to preserve the rust free body forever.

 

Yeah I completely agree, it's worth it to use the rock guard/bedliner under the paing in the wheel wells for that very reason, not to mention it'll help keep the paint looking nice. Mind me asking what you did for the underside of your car? did you use underbody coating? or did you paint it?

 

I didn't do a frame off restoration, so I did it the old fashioned way. Got under there with a wire brush, drill motor and elbow grease. Then I painted it gloss black.

 

Yeah, I'm not planning on doing a frame-off either...but I'm painting my car orange so I'm wondering what would be the best thing to do with the underside of my car...

 

Not a lot of choices with the underside, regardless of what color the top is. I'd say it's pretty much black or maybe silver, but I sure wouldn't want silver. The finish is another choice; gloss, satin, or flat. I chose gloss simply because I can get under there once in awhile and use my long handled brush to wash and then spray it with the hose. Gloss just cleans off easier.

 

So you think its best to get rid of the under-body coating and just paint it black with a durable paint?