Hi guys. I am new to this forum and have enjoyed searching through and reading numerous posts. Incredible amount of information here.
I need a little help with primer.
I am doing some metal work and gap repair on my 70 Challenger in preparation to get it painted late this winter or early next spring. It’s been painted once and I am just fixing a few things right before it gets a real paint job. I want to do as much as I can myself, and let someone do the painting. I have some repair areas that are bare metal that I need to put something on until the rest of the car gets scuffed or sanded and a sealer is sprayed on. I likely will spray the high build primer and sealer myself. What should I use for these spots, because I will likely have to put down a little filler as well?

Are you planning on the full respray being over the existing paint or will you be stripping it all off? If the former then epoxy will seal up those areas; if the latter then it doesn't really matter as long as the car is inside and dry - it will come off anyway.

If the car has been painted before then I'd be very careful of painting over a substrate that may have issues or even be approaching a level of thickness that another coat of paint will make too thick and lead to failure.

I was hoping to just have it sprayed over the existing, as it would be the same color, and I want the shop to use the same brand of paint. I spent countless hours and probably gallons of primer to get the panels flat. I painted the car myself and it has held up well, however it is time to have a professional paint job.

Jsand160 wrote:it is time to have a professional paint job.

If I was your professional, I'd strip it. I don't like the idea of my reputation sitting on someone else's dodgy groundwork.

It's a shame that all that work has to be redone, but I don't understand why you'd go to that effort and then settle for a less than perfect finish.

If it's been repainted only once, then you're perfectly fine to paint over it.
If you are going to prime over any spots that show bare metal you would be
better off using epoxy, for over any fillers, 2K (urethane) is usually used
because it's easy and is a higher build than epoxy so you can block it smooth.
Epoxy can be used for that too, it's just a little slower to sand and takes more to build.
If you do a good "prep" you should be able to get a good paint job, as long as you can find
a painter that trusts your work.