After sand blasting, how to prep for paint ?

[Cranky]

I know this has been answered in another thread I started but the subject matter of that thread was about using fillers on drive line parts and would like for this to be beneficial for others and not just me and the ones that read that thread. Thanks!

 

[super-bee_ski]

I used Prep-sol and then primed the paint.

 

[krowbar]

I use acetone then prime then paint. On stuff that I acid dip( depending on the part) I will self etch prime then paint or use zinc paint alone.

 

[Lbone]

acid wipe rag, sealer then top coat on raw steel OR epoxy primer on raw steel back to back with sealer then top coat. you cant use acid wipe with epoxy its either one or the other. I Have worked in the body shop biz for 25 years this is what sikkens recommends.
2 part epoxy primer is available in a spray bomb with the hardener attached to the bottom of the can its tough as nails but only has a shelf life of about 4 days. I don't believe it contains isocyanates (nasty stuff) and is a lot cheaper then buying a 50 lot tub of acid prep rags. If you want product #s I can get them for you.

 

[747mopar]

I like Epoxy primer over blasted metal, tough durable stuff and keeps it from rusting where other primers don't seam to seal as well.

 

[Donny]

If I'm hired to prime post media blasting, first thing after getting all the blasting media cleaned out of the product is I use dust and wax remover, spray it on, lint free blue rags and wipe down the metal. (You won't be able to do this on sand blasted metal as your rags will tear up). Then, shoot Epoxy primer, two coats. After about 2 days its tough and solid. Some painters don't like working Epoxy because they say it won't sand down good. Today's Epoxy primers (at least the ones I use) allow sanding when/where needed. Add about 10% reducer and it modifies it to behave like a sealer, but, not a U.V. barrier -- so, don't leave it out in the sun.

 

[Lionized]

Wet/dry with rubbing alcohol (wax on/wax off), then tack cloth.
Light (mist) coat of zinc/etching primer then 2-3 coats of epoxy primer.
prep primer as you would normally prior to paint after it has cured sufficiently.

 

[Donny]

Let me add that I used to put a zinc rich primer down before Epoxy, but, I've found that this process the Epoxy will not stick that well to the zinc primer. How do I know that? Well, glad you asked! Often, I have to weld these panels up after this above process, and the heat delaminates the Epoxy. Same process on pure Epoxy, the epoxy just stays in place, burns up a bit, needs a respray, but, it won't peel off. Lessons learned; Epoxy straight to Metal. Period.

 

[zyzzyx]

I agree with Donny, and I like to use DuPont 2580CR DTM Epoxy Primer. It's green and it's a two-part epoxy that can be sanded easily if need be. It has to be "scuffed" if it dries formore than 24hours to topcoat it with primer or a color. Dries very glossy and you can see all of the surface imperfections! I like that alot.