what to do with this
 

to start i'm not a body repair man but (i can do it) with some help from you all, i am a painter though not a pro but well you know lol,my ? is what do i do to get rid of i guess it's called pitting as you will see in the pictures i was sanding my 62 fleet bed tody and ran into this pitting what do i do to make this smooth,and after i make it smooth what next.i have painted some vehicles for people but the body work was allready done .so now that i'm restoreing this truck myself i have to learn bodywork since i can't afford to pay somebody else

Sandblast it clean, then prime and sand, prime and sand......keep priming and sanding until the pits are gone.

Randys method will work fine if there is enough metal left. Looks like some of those pits go all the way thru the metal. If you sandblast it till all the rust is gone you may find something that resembles swiss cheeze. I would cut it out and make a patch panel to weld in.

Yeah, forgot to mention that if you get carried away with sandblasting, the entire truck could disappear. :D

no the pits don't go all the way through there not even rust pits just clean pits,actually it looks like somebody might of blasted a little to close to the panel and caused the pitting if it is pitting i don't know just guessing ,i'm going to sand on the other side tommrrow and see if it's the same way,and i'll let you know. the little holes you see looks like someone might have pulled a little dent out at sometime,the truck body is very solid i haven't found a drop of body filler in it no where,i bought it from jacquesdean from the 60-66 parts board i think he just started sanding in that area and stopped,so i decided to fix it first,before it got out of hand ,

You can use spot putty to fill in the pits, then sand the spot putty , and primer the area.

I'd go with what's called high build, or high mill primer. It is a poly primer that goes on thick, 3 coats = thickness of a penny. Then block sand it.

Chuck

I agree with ccsrcr; pitting is usually filled with automotive glazing putty. That's exactly what it's for. Sand it to bare metal, primer it, then putty. Primering and sanding over and over again would do it, but if you were using regular primer, it would take probably 25 coats or more. Don't know about the high build primer, but sounds like it would work as well.