Rust removal and dealing with pitted metal

[stang1986gt]

My 69 F100's bed sides have a lot of surface rust, and there are large areas that are pitted. I removed all of the rust with a flap disc and 4 1/2" grinder so I can get some primer on the metal (I was going to restore the truck, but now I need it to haul stuff for remodeling so the resto will have to wait). My question is, how do I deal with the pits that are still there? Will these simply be covered with body icing (for block sanding)? I keep sanding but I can't seem to get rid of the pits totally, and if I use a grinding wheel, well, that does more damage than good. Any tips would be appreciated.

[FORDification]

I'm tackling this right now on my box as well. Once rust starts, it won't stop... which means it has to be completely removed. You're going to have to get down to virgin metal at the bottom of those pits for paint (or anything) to stick. I'm planning on sandblasting those trouble spots to clean them up, and then I'm thinking a few coats of primer/surfacer should fill 'em in. If not, then a light coat of filler would be needed. However, if you've ground most of the surrounding areas down to bare steel and aren't planning on finishing the job right away, just keep in mind that the rust process is going to accelerate quite a bit. You need to seal that area from moisture...well, as best as you can. Granted, you'll have to sand it all back off again when you get back to work on your truck, but it has to be done.

[fordman]

you could do a skim coat of body putty. or you could do as i am going to do on holes that have been drilled in doors for mirrors and just spot weld the pits and grind them back smooth.

[FoMoCo]

Sand blasting or using PPG's DX 579 metal treatment will clean the pits. If you need to skim it use a corrosion resistant filler like Z-Grip or a glaze like Metal Glaze OEM. These to ecceed the salt spray test. Remeber fillers are very porous like a sponge. You'll have to keep it very dry untill you can get e good primer on there.

Nick

[stang1986gt]

Great! Thanks for the tips!

[trustyrusty67]

If the area is small use naval jelly on the rust. This stuff will eat the rust, just don't let it dry out and wash it down with laquer thinner when you are done.

[The Good Humor Man]

I bought some stuff at farm & fleet, that you spray on rust, a rust treatment.
I got the rust off the best I could, and sprayed this stuff on, and well in 5 years I will let you know how well it did.
I used the whole can or I would let you know who made it.

[Tech 1]

I guess it really depends on the quality of job and the length of time you plan to keep it. If you don't remove all the rust it is going to rust again. I don't care what you put on it. It may not happen right away, but it is going to do it. My feeling is that the cost of body and paint materials is so high and the work is so labor intensive, that it just doesn't make sense to not do it right in the first place. Having said that, if you just want it to look good for awhile then go for the Rustoleum or whatever.