Thread: Urgent! Just got frame back from sand blaster

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I have a bare frame that I just got back from the sandblasters.I have a few more weeks of work before it will be ready for paint.What can I do to protect the metal.Will it be fine if its in my garage ,or do I need to spray it with a primer now since its bare?

I am going to start boxing the frame ,and would like to paint the inside of it before I box it.Will spray cans work for this?Thanks

I usually shoot everything just back from the blaster with self etching primer.....

Just an amateur here, sitting in front of a screen while I get over a bad cold, but I have two answers. First the best way to do this is to use an epoxy primer. When I received my Vintique steel wheels I had a paint shop spray them with epoxy primer in anticipation of rock chips on the wheels. However I do not know the exact name of the primer. Second when I got my Brookville frame it was totally bare and I just gave it a light sanding by hand and sprayed it with three coats of Rustoleum black enamel from a rattle can(s). That was done in July in hot weather and the enamel dried quickly. I don't think this is the best thing to do but I wanted to get it covered quickly and that was before I knew about the epoxy primer. Now after a year and a half of puttering around the frame it has held up pretty good and I plan to give it a touch up coat here and there before I bolt the body on but you really ought to see some of the buildups by Henry Rifle and C9x to see what a quality paint job can look like on a frame. My excuse is that I am putting fenders all around so the frame will be totally covered except from the bottom and only visible when on a rack. Some of the folks here have beautiful paint jobs on frames of various colors with a finished gloss, so you have to decide whether you just want to get it covered now or get it to a paint shop. Note that just using rattle can primer may not be a good idea since most primers do not seal out water. Primers are intended to be porous to get good adhesion from a top coat. That is why I used an enamel right away, although I guess you could use rattle can primer followed by rattle can enamel. Probably some of the real paint experts will have better answers so wait a day if you can and read their suggestions.

Don Shillady
Retired Scientist/teen rodder

You've got to get some paint on it immediately. Rust gets in the tiny dimples cleaned by the blasting and nothing but blasting again will get it off.

Just my 2 cents worth, when I had my Corvette frame chemically stripped (vatted) I painted it with PPG #90. Its an activated semigloss primer and is very easy to apply.

you can get a self etching primer in a rattle can from pro paint stores that is made for bare metal frames. you can also use a product called POR15 , or eastwood has Encapsulator , and is offered in a chassis kit to do an entire frame . both can be sprayed or brushed on, with unbeliveable results

when ever you expose bare metal to air it slowly begins to rust up again, so dont wait long or like R Pope had said you will haveto get it blasted again.

Originally posted by Dave Severson
I usually shoot everything just back from the blaster with self etching primer.....

Where can I get some self etching primer? Will any paint store sell it to me? I have a gun to spray it.



Thanks guys first time preping bare metal.

[QUOTE]Originally posted by BigTruckDriver
[B]Where can I get some self etching primer? Will any paint store sell it to me? I have a gun to spray it.

yes . most any paint store will carry it. give your local store a call and ask how much for a qt of self etching primer, 1 qt should be enough to do most midsized frames.

I have used grocery store bought vineger it has a 10% acid content that is great to wipe the frame down to remove verylight rust just before you spray the primer on.

.........usually you finish welding before you paint because the heat of the welding is going to burn the paint off anyway. Plus it's easier to weld without paint on it. Why not weld it and then have it powered coated? That will get inside the frame after it's boxed.... Bill

........... 1) put oil on the bare metal so it doesn't rust {this is what the steel mills do so it won't rust in shipping & before it's used}. 2) Then right before you weld it, wipe the oil off with acidtone. 3) Do the welding on your frame. 4) Clean up the welds & prepare the frame for paint. 5) Then paint it..... Myself I wouldn't have had it sand blasted until after I'd finished welding it. Have you considered having it powder coated? This would get inside the boxed rails really well. I don't know anything about painting so listen to everyone else on that one..... Hope this helps ya, Bill

Ps, It's easier to weld it before the paint is on plus any paint that's inside the boxed frame rails is going to burn off anyways..... This is the way I'd do it but then we all know about opinons, huh???

I agree with billlsbird . any welding should be done before painting.

and you cant beet the endurance of powdercoating.
much better than painting.

when I used to work for the local airport as a mech. we would use a product called LPS 3 heavy duty rust inhibitor in a aerosol can. on engine cylinder jugs right after machining to prevent rusting. it sticks to a vertical surface without running down to the floor and can be wiped off with thinner.

Plus if you dont clean the weld surface you will contaminate your weld causing possible cracks later (unlikely) but why take the chance

With a light coat of self etching primer, you can weld over it with only minimal clean up prior to welding with a wire bruch and some lacquer thinner. IMO it's easier to clean a few spots before you weld then have the entire frame get a bunch of surface rust.

Coating it with oil also works, but is a real pain to get all the oil off of the frame and out of all the little nooks and crannies before you paint it.

Epoxy primer will work, but my paint rep has always recomended self etching primer on bare metal prior to the epoxy primer.

I'm certainly not an expert on it, I rely on what the paint company reps recomend........

You first need to get all the fine sand off it- wash it down with rubbing alcahol- then do your welding- if it's in a dry place it will be just fine until you weld it up anyway, as long as your going to weld it within a few weeks. Don't freak out over some small surface rust on your frame- it's STEEL, not body tin, and a wire brush will remove it easily.
If your going to let it sit till next spring then spray it down with WD-40 until you get ready to work on it & then wash it down as above.
Weld & then if your going to paint it instead of powder coat it then etch prime & epoxy seal it. If your going to mould it in do it after you etch prime- but before you epoxy seal.

Washing it down with lacquer thinner works fine.
Acetone works well too.
Important part is not to use any petroleum product.

Keep in mind that if you're spraying epoxy paints a breathing filter is not sufficient protection.
You need a breather with a fresh air supply.
Covering all exposed skin areas is a necessity as well.


I understand WD40 has silicon in it's formula.
Silicon around paint is not good.

Silicon creates never-ending problems where paint is concerned.
For that reason stay away from silicon based waxes as well.