My car was sandblasted to bare metal inside and out. I used Eastwood After Blast.....supposed to be a cleaner and also etches with phosphoric acid. Will be priming with an epoxy primer.

The problem is now there is a chalky white residue in many areas that has to be scuffed off. This is going to be a much larger time committment than I anticipated.

http://www.eastwood.com/eastwood-afterblast.html
According to Eastwood, I should be able to prime without any further prep, but obviously this will not work.

Any suggestions about removing the residue and prepping for primer?

Couldn't you just use "prep sol" before you paint as you should wipe everything down with it before painting anyhow.

From what i understand the acid needs to be neutralized because some paints wont stick to it. Not to mention the physical barrier the powder probably makes on the metal. Phosphoric acid is the same as Ospho brand which you will find alot of info about on line.

prep sol looks like a wax/grease remove, not a protectant against rust, so it won't achieve the protection that I'm looking for. And yes, I'm using wax/grease remover prior to priming but it does not remove the residue.

I'll check on the ospho information.

Thing that's frustrating is that Eastwood says after applying this, you can go directly to primer. NOT

From what I've read you don't use self-etching primer on metal that's been etched, used epoxy primer

that's what I've read also. I'm using epoxy primer


Thanks for the responses so far. I think the residue may be excess After Blast that crystallized

I havent used the Eastwood product, but did use the PPG two step acid etching and metal prep followed by a 2 part epoxy primer. Crazy as it sounds, part of the process is to rise with water and wipe dry. This eliminated most of the 'ash' or white chalky residue. Before priming I did wipe everything down with a prepaint cleaning solvent/wax/grease remover.

http://www.bapspaint.com/docs/psheets/PPG/...ltron/P-226.pdf

I did find in some of my 'testing' that by not rinsing off the panels completely and wiping them dry did leave a white residue. Hope this helps!

That white stuff is from the acid. Had the same stuff on a Bug I used Jasco metal prep on. They say you can paint over it but your residue looks to be pretty extreme. I wiped the bug down with a damp rag and didn't get crazy removing every bit of it. Painted over it with epoxy primer and it stuck just fine.