The Stovebolt Site Forums The Shop Area Paint and Body Shop Primer for Body Patches

Hi all, im new to this forum and just trailered my 58 Apache home on my 65th birthday. In the process of dismantling and journaling what each panel/part needs. I plan to get her down to the cab with doors sitting on the frame and then start replacing rust with new patch panels. Cab corners, rocker/steps, lower doors and lower fenders. This is gonna take me a while cus I’m new to mig. I have one friend teaching me his techniques for miging body panels. My question is this. I plant to fix each patch, body fill as necessary and prime before moving on. Some of these patches could be sitting for a year or two. What can i prime over new patches and body filler that won’t grow rust underneath?? I wont be building the spray booth till I’m ready for final prep and paint. Wayne suggested ospho.

You can get 2K epoxy primer in a spray can. I've used Spray-Max brand with success, although I haven't left parts primered out in the weather. Parts primered with it and stored in my unheated trailer for a couple years didn't rust. Once you activate it, it's shelf life is 2-3 days, but can be extended a bit if stored in the refrigerator.
Alternatively, you can mix up a little epoxy primer and brush it on your patches. You'll be block sanding it anyway.
The Ospho is a rust treatment, not a primer, and you have to be careful that your primer is compatible with ospho, which is acidic and needs to be neutralized at a minimum before you primer.

I would weld in the patches, strip the entire panel to bare metal and epoxy prime with a gun designed for primer.
Doing it this way will allow you to work on your truck piecemeal, one entire panel at a time. When you are done with each panel, the entire panel will be protected and you will have a very good base to begin with body filler, and another coat of epoxy primer to protect the body filler for final block sanding of the entire truck.

Carl's approach is also what I'd do. You don't need to do an entire panel, but spraying a small amount of epoxy is kind of a pain given the setup/mixing/shooting/cleanup time required. That's why I suggested either rattle can 2K epoxy primer or brushing primer on your patch panel.

Thanks for the replies. Been reading and youtubing a bunch about painting as everything has changed since my days af painting and carving lacquer back in the later 70's. Paint has changed as have many of the tools. HVLP replaces the Binks#7. I guess I will need to unlearn what I used to do and start anew. I read that epoxy makes a great sealer. For some reason back in the day, I recall body filler always went on bare metal before paint. Thats why I planned to patch, then body fill, then prime. It also sorta finishes the repair job for a sense of accomplishment. None of these parts will see outdoors again until she is done. I wanted to have all the repairs done before I strip the rest of her down as it has already had two color changes plus a failed clear coat. The repairs are gonna be slow as I am new to MIG. I will look for the epoxy rattle can to see how it works. Not sure how well two parts will work in a rattle can. I suppose I could build a small paint boothe on wheels that can drape over the work area to contain the mess while 'm doing steel repairs. Need to think about that. Thanks for giving me options to ponder.

Ima third on Carl. There's been discussion in some circles that the heat filler generates, then cools, tends to create moisture. It'll get trapped between the filler and metal, causing rust issues until the filler falls off or loses its bond with the metal. Current practices are to seal with epoxy primer, then work your filler on top of that. You can re-epoxy, fill primer, seal or whatever method you choose after that, before you topcoat it.

I hear ya and will look at the issue as more unlearning i need to do. Will seal with epoxy before filler and then cover with epoxy as I’m sure i will sand thru in spots while finishing the filler.
Thanks for the lesson.

Kevin S I was new to the mig also but I purchased a Lincoln and was able to learn in short order, I think fairly well. I have patched drivers and passengers floor pan and side kick panels and one cab corner bottom (the other one is pending). Truck is 65 C-10 Chevy.

I plan to have it professionally painted at some point. I am also doing it piecemeal and my patch work thus far has been interior so I have used Rust-O-Leum Rusty Metal Primer and these areas I will topcoat with spray can to match the interior on these out of the way places. Most will be covered with floor mat. The dash, ceiling, doors etc. will be professionally done.

Good luck with yours.

Thanks for the encouragement. I have a friend rebuilding a 50 gmc that has invited me to apprentice with him. Did my 1st mig welds in his shop and helped him fit a new cab corner and dash. I also just signed up for a welding class at the local community college to gain more knowledge and get some additional spark time before i try burning in pach panels. I’ve set my mind on becoming good at mig.

I took on this project to do the work. I will likely outsource the engine and tranny because i cant seem to control my impulse spending on machine work and parts when i build an engine. Been there, done that. Crates are cheap compared to me. My girl is from my birth year. Brought her home on my birthday. We both understand each other as we are both in rough shape. I look forward to the challenge.

Best of luck on your challenge!

KevinS

Take a gander at MPandC's sticky thread in the tech tips up at the top of the forum on MIG tips. Link. Good stuff. I'm not sure your welding class will adequately cover MIG welding sheet metal, but it may.

I agree about the class. Thats where my buddy comes in. He is replacing body panels on his 50 gmc and I’m working with him. I am practicing on scrap. Already blew my 1st holes in #18. I’ll figure it out.

I did read and will re-read those tips you pointed out.

KevinS, I'm extremely set in my ways when it comes to using my old tried and true tools. As do most folks on this forum, I have amassed many tools but not much in the way of new tech tools. I have had very good results with modern paint products using my Binks model 37 and Binks model 7. I used PPG products in the '70's and '80's, still like PPG and have used their Acrylic Urethane and they still have Acrylic Enamel. I know some will comment on the HVLP equipment, I just use what I have and don't need or want to spend, and I don't want more stuff than I already have. Of course, the small batch mixing, waste, and clean-up are still an issue with using a bigger gun but it works for me.

Thanks 78. Last time i painted was with a Binks#7. That was 45 plus years ago. Going to modern equipment does not bother me. Ill figure it out. Going with modern paint scares the poop out of me. Shooting acrylic lacquer back in the day was easy peezy. I could screw it up, sand and be laying down more coats in a few hours. The lacquer had a depth to it that is unique. I never liked the acrylic enamels, eurethane did not exist and two part epoxy was new back then. This project will never see work again. Its been working its entire existance. Like me shes retired. My garage potato will be pure toy.

I may lay lacquer on her. Have not decided yet. I certainly hope I don’t fire up all the lacquer haters with my statement, because it’s my truck and I’m doin the work. I know i can make acrylic lacquer perfect. Not so sure about the other options.

I've used Acrylic enamel (PPG ALK 200) and it's pretty darn easy to shoot with good results. I have never shot lacquer, though. I use a 3M Accuspray gun kit that I got for about $250, with an assortment of nozzle sizes, and use 3M's PPS system. It makes cleanup pretty darn easy, although the supplies are a little spendy.

I’ve seen videos on the Accuspray system. It looks pretty sweet. Especially the cleanup.

I just got into only my second gallon of wash solvent for my AD rebuild project. I'm close to finish paint - just the cab and a few other bits to go. It takes just a few ounces to clean the gun. The cup liner just gets tossed. A lot less wash solvent than cleaning the paint cup every job.

KevinS, check with your paint supplier, I'm pretty sure lacquer is no longer available. I too was leery about shooting something new to me but was surprised at the ease and great "direct gloss" of the PPG Acrylic Urethane. The urethane isn't as heavy as the acrylic enamel and lays down extremely level with no noticeable orange peel. With the acrylic enamel I would use close to 50 psi at the gun for big panels, with the acrylic urethane being a lighter material I use 25 - 30 psi at the gun, this is with the conventional Binks guns, not much overspray waste and when you stop spraying, the job is done. I'm just relaying my experience, if you still have the Binks #7 and you are used to the feel of the gun, it won't take much to get used to a new material. It may be quite some time before I do a total paint on my '57 but I know I can't afford to have someone else do it, I plan on painting it myself. For now I have a blast driving it and doing the little projects in between. You'll enjoy the old girl. We're neighbors, I'm in the Wolverine State.

I agree. I find the urethanes user friendly. As an old painter, you'll find everything easier, too. Toughest of any modern paint job is the price of material.

Follow the tech sheet that comes with your product, mix ratios, substrate temp, flash times, and you'll do great!!