Taking care of rust

[gbarrett]

I took my Cherokee to the body shop this morning and did the prep work for a quick paint job. At this point, my friend, the body shop owner, said he would take care of the body damage when things slow down a bit, he just wants to improve the look. So, my $450 Cherokee is getting fresh paint.
My question is this:
The truck has quite a bit of surface rust on the roof. I sanded all the loosed stuff off and put a healthy dose of ospho on it and let it set for an hour or so then lightly sanded again. Should I do something else? It won't be painted until late Monday morning, so I can stop by there and take care of something else on my way to the office. What else, if anything, should I do?

I'll post pix on Tuesday of the before and after stuff.

Thanks,
Greg

[DrChop]

I like to use that spray-on rust converter stuff over bare metal that has had the rust sanded off. I typically sand until it's all shiny, then tack and shoot the converter in 3 light coats, waiting about 20 minutes between coats. This usually will turn the metal black, proving there is indeed rust that has now been neutralized.

Extend is my favorite, it's what I shot the '28 panels with after 2 weeks of sanding the rust off by hand. I used the Mar Hyde brand when Wallyworld stopped carrying Extend, but they all work the same regardless of brand. You can fill and paint right over it with any brand of body shop supplies.

Another thing. DO NOT, ever, wetsand the car until AFTER your finish paint coats are applied. This especially goes for primer-surfacer coats, and any plastic filler. These materials are porous and soak water up like a sponge, rusting out the metal underneath in a year or 3. Once you have a finish coat of paint on the car, it will render the underlying coats impervious to water penetration. Dry sanding works OK, just be sure not to let the paper load up. You can finish-wetsand your color coat after a week's drying time, to let all the paint solvents evaporate off. This will rid the finish of orange peeling, and give you a baby's-butt smooth surface for the clearcoat, or wax, if you prefer.

Doc