I searched but could not find the specific info I'm looking for to do this without making a frame off job out of it.

I have a 78 F150 4X4 that I'm going to have to paint since my wife is too attached to it to let it go. We bought it new and now it's like an old sway back horse that she can't stand to see go to pasture.

We are in Texas. The heat of the last 27 or so years has caused HEAVY surface rust, but there is no cancer. I really kind of look forward to painting it, but I just don't have time to do a frame off restoration and spend time on each panel separately, etc.

I have a few DA's and a 5 HP, 30 gallon compressor. Is my best bet to just start going after it with a DA or would I be better to get a sand blaster. What grit, 180? What type of media for the sand blaster? I don't have a way to recover it, so if a sand blaster would be far superior I need an affordable media.

There is very little body damage that needs to be fixed other than replacing the left front fender. There is aged, serious hail damage on top, a few VERY large dents, but I think I can straighten them pretty well.

So, to get off the surface rust without tearing apart the truck, what are your suggestions?

Thanks

 

Sand blasting is excellent, but it can get a bit costly. The compressor you have will probably hold up to blasting but will be very slow and frustrating. Sand it about $4/50# bag and you can count on about 10~15 bags min.

Chem striping is a pretty good option, but wont do much for getting the rust off. A good sanding will help a lot, but still not as good as blasting.

I'd concider getting a $10 plastic tarp from Harbor Freight and laying it out to recover the sand.

Here's my setup:
40# pressure blaster from Harbor Freight at $70
5HP 30 gal + 20 gal second tank, belt driven with 33% overdrive pullies.
5 gal plastic bucket with screen door mat streched over top and lid on top with large hole in lid.
Broom and coffee can to gather sand, drop into screen of bucket and shake bucket. Poor back into blaster. Simple and cheap

Sand blasting WILL remove the rust, sanding can't get into all the small areas and doesn't do the same job except maybe on a flat open area.

Other option:
Sand as best you can, use phosphoric acid ($6/qt @ home depot) several times over several days, sanding after it's dry. Using other tools, screw driver, sharp nail, scraper, etc... remove all the rust you can and retreat with the acid.

This should put the rust in check and a few coats of epoxy primer should do the trick.

Paint the truck with something after the primer even if it's just cheap paint, as the primer is not good for long term storage.

The acid should be done either way, the result of the acid should be gray / dark gray / black surface. Redish / rusty / orange should be retreated. Suface should be dusty dry when done.

 

Thanks very much for the reply.

Well I went out and looked over the truck very closely. I think that I can DA most of the rust since it's in flat, open areas. The rust that I can't sand is on the drip rails and it's pretty extensive. I guess this might be a combination of sanding and sand blasting. This means I'll have to take off the aluminum drip rail trim, which makes it look more like this truck may take a lot more disassembly than I planned on.

I've learned from the paint jobs I've done over the years that the more trim and stuff you take off the better the result.

Thanks again,
Doc

 

If the truck is now "family" , go ahead and do it right. Forget the chemical strip, too messy, and if ALL of the stripper is not nuetralized and removed from EVERY crack, you will get paint peel later. Auto paint is HIGH dollar stuff now. just want to paint it once. ....

Sand/media blasting is good for heavy metal parts, but large pieces of sheet metal can be warped quickly from the friction it produces , and you wont see the warpage , until you start blocking out the primer coats, too late . Buy or rent a 7 in side grinder , get a pad for it and 80 grit paper, keep it moving at 1200 rpm, to prevent heat warpage. . That along with your little Da's and a lot of hand sanding in contours, will take it down to metal fast....

A old truck will have rust hidden, not good to put new paint over it, get it down to metal , then you know what kind of foundation you will be starting from. A new paint job is only as good as the weakest link in the components, and that includes what the first coat of primer is adhering to. all jmo

 

Have you looked at PICKLEX-20 !
Good luck,
Jim in or.

 

Question for Karlijay or other experienced with sand blasting....When you go to re-use the sand,, do you just pick up what you think is the cleanest sand ?? will the old paint or rust particles hurt your body work??I'm not understanding what kind of screen your useing if your sifting, thanks, Bruce