Hi,

Any professional guys...please answer one question.

Is there a rattle can primer that I can use on bare metal as the initial coat...
The issue is that I will be doing lots of metalwork on the teenster...and this takes lots of time.
I will have one rear quarter done this week...loads of welding/grinding and hammer dolly work...I really dont want to see it flash rust.

I would like to seal up each panel as I complete the initial metal work.
I will come back in one session to flatten these panels with filler etc.

I am hammering all the dents out, just want to keep it rust free and I need something with great adhesion..

I am ok if I need to spray a sealer over everything prior to the next phase of paint ....

IC rattle can auto primer at the hardware store....is that any good?

I can go to the auto paint store and buy the high end primer in rattle cans, but its really expensive and most of it will get sanded off later on so I would rather keep the price down on this issue to start with...

Rich

When I did my car I had bare areas open for a couple months while I did all the work and then used a metal prep to etch and remove all the light surface rust before primer. As long you have it in a garage it should be fine. The first coat of primer should be the best primer you can afford as this will be the foundation and to all the other coat.

I've used "bondo brand primer" on my car initially, I purchased it in the auto section of my local hardware store. I found the quality and price pretty darn good.

Rich,

I was at Walmart the other night and saw a self etching primer in rattle cans in the automotive section of the store. I didn't read the label but it should do what your trying to achive.

Any new photos of the roadster? I've been out of town.

I'd recommend an epoxy primer
it's water proof

most primers can bleed moisture
not the kind of thing you want under your paint job
you wouldn't beleive the number of rust dots I found under my 2-year valance paint job.

a harbour freight gun
and an epoxy primer (not rattle can)
one panel at a time

catalyzed primers can't be mixed into a can... only old school primers that air dry (solvent dry) can be can mixed

b

I would use self etching even though it costs more. The hardware store primer has a nasty tendency to lift when you put something else over it. The self etching primer won't cause any problems later and it will solve your problems now. No aerosol product is even close to as good as the gun sprayed counterpart so the aerosol self etching primer will allow rust to form if it's outside for a couple of weeks. If it will be getting wet you will need a catalyzed epoxy sprayed from a gun. If you sand it you can even put filler over epoxy primer. If it won't be outside the aerosol will be plenty good enough. If you buy cheap ass primer it'll be like $5.00 a can, self etching will be more like $15.00 a can. That's only $40.00 more for 4 cans if you even use that much, not a lot in the overall costs of materials. I wouldn't even use any spraycan hardware store primer on my kid's Pinewood derby car. I actually used UV cure primer on that. Cheap primer will cost you later if you are unable to sand damned near every molecule off.

I've used Jasco metal prep with great results. I stripped a 62 sliding rag top bug to bare metal. I then used the metal prep. I had a pair of bare doors sitting around for more than a year without a hint of rust. That way you don't have to keep spot priming your work. Just keep a diluted bit handy and re apply when needed.

I used a lot of rattle can self etching primer ......RMS 710 IIRC....not cheep at about 16 bucks a can at the automotive paint store. Very convient for small areas.....some not so small..... compatible with just about anything. I ran with the stuff exposed on my hammered flare job for a couple-3 years with no rust.

When I took my car to bare metal I did use a spraygun etch primer for the large body sections but went right over the top of the rattlecan stuff in some areas with no problems......but I'm just a backyard hack painter.....engine builder, fabber....WTF do I know?

I only use rattle cans for small fixes. Get a gun for anything large. If you use a high build primer that will lay down a heavy coat, it will give you a thickness that may be sanded to eliminate small problem areas. Its kind of like spraying very thin bondo. Make sure your appling it over a clean surface. No primer over cheep rattle can spray! That combination will just cause more problems. The cost of good primer in a can is really high. If it's just a spot here or there, I use acid #8 etch primer, but it does run about $15/can and it doesn't go very far.

Eastwood products carries many high grade primers in rattle can form. Just got their catalog today.

Steve

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Paul

You could use a zinc phosphate coating like POR15s 'metal ready'. Its really easy to use. Should keep the rust off until you prime & paint.

SMD

Or just brush on some Ospho.

I'm just a hobbiest but I've been painting my stuff a long time. Ospho is good but it will need to be wire brushed off or removed where it leaves a scale or the paint will fall off in those spots. I use ospho on a metal work bench in my shop and it looks like stainless. When something does rust it I just put some more on that spot. Epoxy primer will seal the metal and stop rust from forming under the bondo. The only thing is it will need to be scuffed after it sets over 24 hours to get the new stuff thats going over it to stick. When I sand the filler down I spot paint the bare metal with more epoxy primer. Good epoxy primer can't be removed with laquer thinner and will stay on even when you hammer out a dent. I have bought some shopline made by ppg that is not very good stuff. Their sanding urethane surfacer is pretty good. You can usually tell how good a two part paint is by how hard it is to clean out of the gun. Epoxy primer is usually a non-sanding primer and that means it will usually ball up when you try to sand it. I do sand it but the paper really loads up and must be cleaned off after only a few sand strokes. If you don't clean the paper the built up paint on the paper will gouge the surface and make long scratches in the paint. I wouldn't recommend any rattle can for a basecoat on a paint job. Usually the solvents and catalyst will wrinkle the cheap solvent based paint causing a real mess.

Rather than deal with the ospho getting in cracks and causing problems I would bite the bullet and use a epoxy primer (two part) and not worry about what might happen. I do use a lot of ospho you can tell by the spots on my shop floor.

I once used so much ospho on a 42 ford jeep that I worked on over a year that I had to reblast it to paint it.

I am still searching for a good epoxy primer that is reasonable in cost. Ever since ppg went to the lead free dp primers they aren't as good as the old stuff.

I am painting a 72 bug for my son and the price of ppg's best clear is about 360.00 for a gal of clear and the catalyst. I picked a shopline clear that is 1/3 that. I'm sure it's not as good but it will have to do.

I'd rather spend a day cleaning off some measly flash rust than risk my new paint lifting/reacting with the 'quick-fix'. Or worse yet, having to sand off all the 'quick-fix' primer and having that take much longer than just sanding off the flash rust.

Short Version: I'd leave it bare.