I bought a '34 chevy coupe, its in red oxide laquer primer. wondering if I can spray the epoxy primer over the laquer, I want to do a base coat clear coat paint job.
Take it down to metal and do it the long way around. Mixing different types of paint can lead to peeling and other paint problems. You've got a nice looking car, don't mess it up by taking "short cuts". Do it right = Do it once.
You can spray over the primer without issue. Here is the deal though. The urethane primers are much stickier and will hold to the body better than the oxide primer. If you spray over the primer it will hold only as good as the primers ability to stick to the body which is far less. Take it off and do it right as the previous fellow said. You will be glad you did.
Use that primer like a guide coat ? Lacquer primer likes to shrink, depends on how long its been but when it shrinks down into the deep sand scratches it shows thru on the finished surface.
Or do the rest of the job using lacquer primer, and have a very traditional looking paint job in 10 years as it shrinks and cracks where it's too thick. btw there are plenty of cars around that have lacquer primer on them, and the paint is still sticking to most of the body. My wife and I each have one, painted over 20 years ago
The important issue, as stated above, is adhesion. It would be impossible to know how well the previous owner prepped the sheet metal prior to laying down the primer. That is the big question. I'd strip it and start from clean sheet metal. I wouldn't take a chance.
Some 80 grit will get rid of that primer quick. I have been down this road....lacquer primer is a bad foundation to build upon. The stronger solvents from the products you are putting over it will cause it to potentially fail. Get out your long block and some 120 and block till your hearts content...get off as much as you can...tHan hit it with epoxy
Check with the manufacturer of the primer you intend to use before you go that route. A lot of the paint mfgrs will not warrant anything that's been soda blasted due to a history of adhesion problems.
My biggest concern with lacquer primer is moisture hold out. Some of the lacquer primers didn't hold out moisture very well and might introduce rust. If there was sort of sealer or paint applied and then primer over it, there wouldn't be a problem. But I'd sand it down and do as suggested.
Hey, I'd go with 3-4 gallons of aircraft paint stripper over the soda blast route. I wouldn't suggest you DA off the old finish as that will fill your shop, and your lungs with all that red oxide & the lead contained therein. This will save ware & tear on your compressor , too! With the money ya save by not havin this thing soda blasted, ya can step up to a full urethane primer. Today's epoxies don't offer the protection the old ones containing heavy metals did. " Meanwhyle, back aboard The Tainted Pork "
I'd be more inclined to strip it to bare metal to insure you don't have any rust issues or boggled repairs that need correcting. Those are the ones that are cheap to fix now, not so much after laying down the expensive paint.. Unless you knew the previous owner and had a hand in the priming, you have no idea what's underneath.
MP&C I stopped at the local paint supplier, they said I could spray over the laquer as long as the bare metal body was treated correctly before primmering I could use the epoxy primmer on top of the laquer
You can but it makes no sense at all in the long run. Like building a brick house on a wooden foundation. & MP&C is telling you a version of my story at the moment. What a PITA not to mention the ass ache in the wallet.
Primer has one m in it, not two. If you're going to put a lot of money/effort into the paint job, then start from bare metal. If you're just wanting to put some color on it, with the least amount of work, then go for it. Don't expect it to be perfect or last forever.
Grit your teeth, bite the bullet and do as recommended here. You want to start by knowing exactly what's under that red oxide.
Check and see if someone in your area does "wet, or dustless blasting" using crushed glass (and lower pressures) it creates none of the problems associated with soda or sand blasting. Do it once, do it right. Good luck!
At this point, the only person with the answers to the above in bold is the guy who sold you the car. But I think all of us have seen quickie primer jobs on cars for sale, only to hide something. If you're OK with not knowing, spray away. At the least I would look for the trouble spots and sand those to metal. You need to do what you are comfortable with, within your budget, and within your plans for the car. If you plan to flip it in 6 months, who cares, paint it. If you plan to hand it down to your kid, make it last.. I think the responses you are getting here are trying to save you some headache and wasted time and money down the road from a short-lived paint job due to the possibility of hidden issues. At this point you bought the car, a little bit of red oxide primer should not mean that much in the overall scheme of things. If you knew some history of the car first hand, or if the previous owner could show a build thread somewhere of exactly what was done, then that would be something to consider. Otherwise, I personally would want to see exactly what I was dealing with. Any project that leaves my shop has my name on it, regardless of how it was when it got here. So I need to know full well what is under the paint. The present project I have become rather familiar with every square inch of it in it's bare metal form: At the end of the day, it's your car. You do what you're comfortable with and it's still your car. And we'll still be here to offer advice. .
The paint supply will sell you anything !! Even primer with 3 or 4 Ms There is RUST under lacquer primer !
tonight I spoke with the older gentleman I got the car from. I asked him what steps did he take when he did the bodywork. he told me that he striped the car completely to bare metal, then used steel panels for the rotted areas. and duraglas. he then told me he washed the entire car down with metal prep. before primering. I took auto body in high school, so I know you use metal prep. on bare metal before primer.
Not one person has told you to leave it on yet you are still coming up with reasons to not remove the primer. What is the point of asking for advise if you don't want to take it?
Sounds like you want to use the lacquer primer that's on it, and you trust the previous owners prep, tcpglobal sells lacquer pretty reasonable, what the hell, shoot it, worse that can happen is the paint falls off and you have to blast it to bare metal anyway. http://www.tcpglobal.com/restorationshop/rspaclac.aspx
Hey, Once you remove the primer, remove the ''Duraglas'' and repair those areas correctly with good metal welded into place. The polyster resin contained in the Duraglass, and other half-assed repair methods of that kind won't hold up well under your BB/CC paint job in the years ahead! The fact that the old owner used metal prep prior to primering doesn't warrant that the metal beneith the lacquer primer hasn't rusted. Lacquer primer, that's been wet sanded, or hasn't been top coated with a finish, will act like a sponge when it gets wet.
Sand the fucker good with 150 grit, prime it with urethane primer, guide coat it, block it again with 150, prime again, wet sand with 400 and paint it.. JMO.
If 50 people tell you to jump off a bridge, will you do it? Don't go down to the metal. Do like Lippy says with one exception, don't wet sand primer, dry sand.
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