OK, I'm thinking about starting body work on my cab. For this first question, let's ignore the fact that there are about 20 areas that need major sheet metal repair, and assume all the metal is in good condition.

If I grit blast my whole cab, then I need to clean out all the grit and wipe down the surfaces before primer gets applied, right? How do I get into all the areas such as between the edge of the roof panel and the cowl top section (see the illustration below)? What does everybody else do, just blow out the dust, wipe down what you can, and spray primer everywhere in hopes of hitting most of the metal up in those areas?

 

Yep! Compressed air to blow the loose grit out, quick wipe with some thinner, then prime. Now days, most use a thin layer of etching prime, then epoxy primer as a sealer.

 

Mike, I'm not as worried about the wipe and etch/prime process as I am about the fact that I'll never get a wiping rag back into some of those areas. After a good grit blasting, they will be bare metal and I'll never get them clean enough for any sort of paint to stick. Should I just not worry about it and assume whatever rust starts there will be minor surface rust?

 

I just want to watch this thread George. Thats a very good question.

I thinks its really cool that you are getting back to work on Earl. he deserves it and you need to have some fun as well. I read the entire diary right after I joined and it was pointed out to me.

 

George -

I am familiar with that area. I had to check it out for the drip rail shaving I plan to do. It is a small area that is hard to reach and the edges of the cab top, drip rail and cab come together there pointing edge-wise at you. Basically, I would always use a brush-on where I couldn't be sure to get good coverage with a spray. If it is hidden later, all the better. That is what I plan to do on my 56 in that recess.

I have become a big fan of Herculiner. For areas like that, I'd grit blast, blow it out, wipe it down, then BRUSH on Herculiner. It is waterproof, so no rust is going to form. It is also very thick and spreads well. It is also an excellent insulator for an area like that.

The other option I would use is Zero Rust brush on. I found some at a local paint supply store. Goes on pretty thick and is perfect for that application.

 

Ford didn't worry about it, but that's not a real good go-by. I like to use a cheap brush and something like Rust Encapsulator, just slop it in there generously and vigorously. I'm presuming these are all areas that aren't visible?

 

some of the areas had no paint at all ,when new

 

George-
About all I know you can do is blow it out real good with high pressure air. Then spray a heavy coat of epoxy primer up into those areas. I guess you could take a spray bottle and fill with laquer thinner and spray into the areas before you sprayed the primer. Just give the laquer thinner time to evaporate.

 

OK, the Herculiner or Zero Rust application sounds like it would work.

1. I can work on the various metal repair locations on the cab until I get them all done and ready for primer and filler.
2. There will be some surface rust on the steel in various locations by the time I'm done with step 1, but I'll get rid of that when I grit blast the whole shebang
3. Blow out the whole cab to get rid of as much grit as possible
4. Wipe down whatever surfaces I can reach
5. Paint the hidden areas with whatever goop I choose (Herculiner, Zero Rust, epoxy primer, etc.)
6. Wipe down the rest of the steel again and get a coat or two of primer on it to protect it

From there on it's filler and sanding if I understand correctly.

 

How wide is that opening? Jeez, I going to be media blasting my cab in the spring so I'm kind of interested in this topic as well. If you can spray up there, I would probably use a rust encapsulator. Eastwood sells a good one in a spray can. You can prime on top of that.

 

Earl, I figure if the sand can get there, so will the primer/paint. I've also smooged in places with a brush that I thought wouldn't cover well with a gun. In some cases I've pushed in metal fill epoxy to seal it, all depends on what I think might happen later.

As mentioned above, even the factory (at the time) had a lot of bare spots, far cry from today...but that's why we replace all the metal and wonder "why is there rust here"?

 

George,
FWIW, after alot of reading and some experimenting with smaller items, my plan for the cab is:
1) Dissasemble to a metal shell
2) Take it to a commercial media stripping outfit, get it stripped down to bare metal, possibly with baking soda.
3) When it comes home, thoroughly clean any remaining blast media, first with a high pressure washer, then with a compressed air wand, focusing on the hard to reach crevices.
4) Spray on a healthy dose of phosporic acid based metal etch solution over whole thing, including the crevices. (Hoping to get at any rust here that the stipping process missed, as well as etch the other areas.)
5) Repeat the pressure washer/compressed air routine to get the metal etch cleaned off.
6) Dry the cab by letting it sit in the Texas sun for a couple hours.
7) Rub the metal down with a wax/grease remover.
8) Hand brush black Zero Rust into all the hard to reach spots that will not be visible later, including the spot you mentioned. Let the ZR dry overnight.
9) Epoxy prime everything (PPG DP50LF), including over the areas done with ZR.
10) Spray high build primer over the DP50LF (after the recommended drying time for a good chemical bond.)

I plan to do the body work in slow time after that, sanding away the primer as required for welding or filler application, then re-priming.

I used Zero Rust on my Mustang floorboards about a year ago and it's holding up great, including an episode where a fair amount of hydraulic fluid from the convertible top pump leaked all over under the back seat. The hyd fluid sat on the Zero Rust finish for a couple months before I noticed it, then just wiped right off with no damage to the paint. Tough stuff!

 

One note,

At the begining of this this thread there was mention of applying self etching primer and then epoxy primer. The epoxy primer I use, and I assume others, warn against applying epoxy primer over self etching primer. There must be some chemical reaction.

 

an excellent idea, blow the stuff in there with a hose if you can. I have used this method for years and up to now have not had a complaint!! Good luck

 

I prefer to use a strong vaccuum cleaner along with the compressed air for cleanig out the residue. Vaccuum first then compressed air then vaccuum again. To me just blasting it with air alone is like using a leaf blower on your yard, mostly you are just moving the debris from one place to another without actually getting rid of it, and eventually it comes back to haunt you.