The Stovebolt Site Forums The Shop Area Paint and Body Shop Does anyone use metal prep any more?

Years ago we use to use metal prep (Zinc oxide) on the bare metal before priming. I don't hear of anyone using it anymore. I have talked to body guys that are friends of mine, that have never heard of it. leaves like a galvinised finish on the bare metal. We use to scrub it into the metal with scotch brite pads.

DuPont makes a metal prep that you wash the surface with it then rinse off with clear water before it has a chance to dry. I then use a self etch primer it is zinc oxide in color, then the primer you are going to use before top coat

Red oxide is still around. I have several cans in my shop. Time marches on though and the stuff I use now is called self etching primer under base coat-clear coat. I purchased some yesterday for a '39 Packard complete dash I'm restoring to the orginial wood grain. Since the pro's get $200.00 for a glove box door alone I'm doing it myself. I sure as heck don't want to see this paint start to peel or chip.

The stuff I am talking about is more like what bondo man is saying.It is a clear liquid to prep the metal, Not a primer, you would prime after. like a extra step before priming. I believe it was a zinc oxide liquid. I'm pretty shure it was called metal prep.

I have a product from Zero-Rust called "Prep-Step" I'll be using on my 53. Sounds like it does the same thing you're refering to.

Rust Master, you are referring to phosphoric acid. Turns the rust into iron phosphate. It comes in various concentrations and a few auto body suppliers still stock it. There are safer products out there though.

A word of caution that if you do decide to use it, you have to be real careful with it. Acid resistant gloves and an air purifying respirator rated for acid fumes is a must. Along with good ventilation.

And be sure to neutralize it with a baking soda and a clear water wash. Any left over acid or soda can play havoc with anything you use to coat over it.

I've also heard of some navy guys that swear by Naval Jelly. I tried it a long time ago. It is basically the same product, but in a gel form. In my opinion it makes more of a mess.

This is what I've been using on bare metal before epoxy primer. So far I've been happy with it.

http://www.autobodystore.com/r-o-n.htm

Bob

For the most part metal prep is a thing of the past. Most body shops use a self-etching primer, which eliminates the need for metal prep.

Thanks, Thats what I thought old school technology. I have been out of the body buisness 15 years (worked in a body/restoration shop while in high school/colledge) we were using the metal prep, but the varaprime etching primers were just comming into main stream then. Epoxy primers were fairly new. Yes we did use acid gloves, no resporator, good ventilation though. I was too young and stupid to wear fancy resporators then. I would now!

Ospho, aka phosphoric acid, is used by my body shop after wire brushing and sanding and prior to applying the etching primer.

We used Ospho on the ships in great quantities. Phosphoric acid converts iron oxide (rust)to iron phosphate, which is inert or stable. You can find Ospho at most hardware or marine supply stores. For more details about this product take a look at Ospho

I hope this is not considered advertising as I would hate for the zookeeper to lock me up