Hi guys, it's been seven years since I've done any painting, but I'm back on my 1968 fastback and have some questions, mainly because it's been so long. If you were here seven years ago, I'm the crazy person who painted stripes on the undercarriage of my car.

I need to repaint the rear axle now and need some advice. First, I'd like to smooth the welds on either side of the pumpkin. I had someone (who doesn't do bodywork) tell me it would flake off. Is there really flex at these locations? My plan is to use thin layers of Metal2Metal with a final Evergoat glaze topcoat. Is this doable?

Another question is do I need to totally respray primer on the axle? I've only sanded down to metal on the small areas that had paint damage. Or, can I use a spray can primer on those areas? I will be using single stage, metallic Sapphire Blue, just like it is now.

If I do have to do a total spray of primer can I use my detail gun, or is primer too thick for that? I'm out of paint cups for my big gun and hate to have to buy a big supply that I'm not going to use.

That's all I can think of for now. Thanks for any advice!

Since no one answered, I'll venture to give you a non-expert opinion and maybe this will bump your post up and someone else can answer.

I would think if your cover is welded, it is not going to flex so you can paint it. However, because of the exposed position of the diff,I think you should use a good epoxy primer to prevent rust and ensure adhesion.
You can thin epoxy and spray it through a detail gun. Another option is that HF sells 6-packs of universal disposable spray gun cups for about $7. They work pretty well and that way you could use your full size gun.

Is the existing paint a two part urethane? If it is, you could degrease and sand the bare metal with 80 grit. Lightly sand the existing paint and spray the whole diff with epoxy and then your single stage 2-part urethane. I would spray the whole rear end as it looks it has chips and scuff marks. You might want to wipe it first with reducer to make sure the paint doesn't come off on the rag. If it does, you should sand it all off before applying epoxy.

If the existing paint is just enamel, I guess you could just use rattle can primer and then enamel paint on top of it but with the likelihood that it will rust and chip faster than epoxy and a 2-part urethane.
I would not use rattle can primer under a 2-part urethane.

If you are only "polishing" the welds you should have no issue. I would not take off any more weld than you have to, as you will lose strength. You should have no flexing issue especially with a properly set up spring assembly...

I've decided not to do any grinding on the welds due to the risk of opening pinholes and/or weakening the welds. So, it will be Metal2Metal to smooth everything. The paint that is on there now is single stage Centauri, which I understand no longer exists. The car is bc/cc, but I don't want to do that on the axle. I'm headed to the paint store tomorrow to see what is available.

this nine inch ford was done about five yrs ago, cleaned up with a wire wheel , a pass or two of epoxy, then filler and painted

Thanks, that looks great!

norunz wrote:this nine inch ford was done about five yrs ago, cleaned up with a wire wheel , a pass or two of epoxy, then filler and painted

Did you clear coat over the color? I'm trying to decide whether to do that or not.

Blasted clean fresh Seals and just a couple coats of Epoxy

Before axles

Thanks, I really like it.

Where did you find the gold u-bolts? Those would look great with my blue axle.

yes, we clear coated it, you can`t tell from the pic but it has fine metallic in the paint