Stripped some panels and used Dupont (244?)Quick prep. Used laquer thinner to rinse off. There is a gold tone on the panels now - actually looks like the beginning of rust. Is it rust, or is it a coating of some sort?

It was humid in the garage, so it wouldn't surprise me if it was rust.

It is rust(oxidation). The quick prep is an acid solution as are all metal preps. Acid in higher concentrations speeds up the oxidation process. Personally, I don't like to use metal preps for that reason. Instead, I use an etch primer on bare metal. That eliminates the messy steps of applying metal prep and washing it off.

You've got it Vettefella, metal conditioners like this are like bias ply tires, HISTORY. Etch primers are the way to go.

DuPonts "Variprime" is a fine etch primer. No touching it with your hands, no wipeing, no flash rust. Just mix it 1:1 and shoot a couple of coats and then urethane or epoxy prime without sanding (if you recoat it within the time frame on the tech sheets) and that is all there is to it, MUCH easier than the "conditioners". smile.gif

By the way Uncle, the tech sheet for that Dupont conditioner says to rinse it with water I believe, not lacquer thinner. If you want these to go smoothly do EXACTLY as the tech sheet says.

I don't know of a DuPont 244. If it was 224S then it actually is suppose to leave a zinc phosphate coating (kinda white looking) on the metal. You're rinsing it with lacquer thinner may have stopped this from happening. DuPonts 225S leaves no zinc phosphate and would flash rust as you have experianced even when used correctly if you have high humitity there in your garage.

Originally posted by MARTINSR:
You've got it Vettefella, metal conditioners like this are like bias ply tires, HISTORY. Etch primers are the way to go.

DuPonts "Variprime" is a fine etch primer. No touching it with your hands, no wipeing, no flash rust. Just mix it 1:1 and shoot a couple of coats and then urethane or epoxy prime without sanding (if you recoat it within the time frame on the tech sheets) and that is all there is to it, MUCH easier than the "conditioners". smile.gif

By the way Uncle, the tech sheet for that Dupont conditioner says to rinse it with water I believe, not lacquer thinner. If you want these to go smoothly do EXACTLY as the tech sheet says.

I don't know of a DuPont 244. If it was 224S then it actually is suppose to leave a zinc phosphate coating (kinda white looking) on the metal. You're rinsing it with lacquer thinner may have stopped this from happening. DuPonts 225S leaves no zinc phosphate and would flash rust as you have experianced even when used correctly if you have high humitity there in your garage. Good stuff guys! I did see the info about rinsing with water, but when I had done that previously (different project), it had also oxidized. Talked to the guy at the paint store, and he recommended using Prep-sol or reducer. Anyway, I DA'd everything again and used the 615/620 Variprime. I agree, it's a nice product.

Thanks!