I have a question about painting over an old lacquer job. Nearly 30 years ago, my father's 34 Sedan was stripped to bare metal, primed, then painted with several coats each of silver and clear acrylic lacquer. It was never buffed out and has sat indoors since that time. (He lost ambition and never finished the car). I'm now finishing the car and hate the color and wish to repaint it....so, given that the paint is in good shape(not cracked, crazed, etc) , what would be the recommended course of action for repainting it? Acrylic Lacquer? BC/CC? If I go BC/CC I'd imagine I'd need some kind of sealer between it and the lacquer.
show us some pics.....are you sure its that bad....some people would kill to find cars with presentable old paint......
sounds like a scuff and squirt job to me. talk to the guy you will be buying your paint from to be sure.
When I painted my Merc with a 2 part sealer/primer it turned the early 70's laquer primer under it to dust. The primer that turned to dust was beneath a coat of enamel. Vapors went right thru the enamel & into the primer. That was after 2 weeks of block sanding. Ended up stripping the whole thing with razor blades...not a pleasent job in the least!
you can sand it down and spray anything you want over it . enamel is the one you have to watch out for. you can spray enamel over laquer but sometimes there is a reactivity problem spraying laquer over enamel. stick to modern urethanes and youll be o.k. as far as a sealer goes you should use one technically but i wouldnt bother.ive sprayed lots of stuff and havent had a problem.
strip it,,30 yrs old..sooner or later that paint will fail,if not allready.then guess what happens to all of your expensive shiny paint on top of it..
If the prep work was done right the first time? Then you should have no problem re-painting it with Lacquer . Or sanding and sealing and painting with anything.--TV Things I'm looking for: 2 Riley carbs or 2 Flin carbs
I'll add some input here. I'll kind of oversimplify but cover some basics. All finishes fall into one of two categories: Soluble or Insoluble. Soluble finishes dry by evaporation of the solvent that was used to make the paint thin enough to spray. Lacquers fall into this category. The opposite of this is obviously the "insoluble" type of finish. Insoluble finishes are typically finishes that have been catalyzed with an isocyanate activator or hardener. The drying in this type of finish happens through a combination of evaporation of the solvent and a cross linking of the molecules. Once dry and fully cured they can no longer be redisolved and have very little ability to soak up a newly introduced solvent such as in a repaint. Enamels, Epoxies, and Urethanes are typical examples of insoluble finishes. The problem with painting anything over a refinish lacquer (or soluble finish) is that they will forever absorb a solvent no matter how long ago it was painted. Whether it is the basemaker from a urethane paint, more lacquer paint or the solvents in a sealer, the soluble finish will soak up the solvent that is in whatever you are spraying on top of it. This causes the soluble paint to swell up as it absorbs the solvent. Problems may not show up initially but as these solvents once again evaporate back out, the soluble finish underneath the new repaint shrinks. Maybe a few months down the road, maybe a few weeks. You might see sandscratches, checking, crazing, etc. The likelyhood of problems is increased depending on the thickness of the lacquer underneath the new finish. Typically painters would spray numerous coats of lacquer to give enough film thickness to allow for sanding and polishing so the paint on your car could be several mils thick. I've had mixed results sanding the lacquer down and spraying a good coat of 2k primer allowing a good long dry time to allow all the solvents to evaporate before beginning blocking and then applying a good sealer before refinishing. As I say it all depends on how your paint will react. Best advice would be to remove the paint down to bare metal and work from there out. If you really want to repaint it this would give you the best base to start with. Or you could try rubbing out the finish thats on the car now and leave it alone. Hope this helps.
When we were doing bodywork (20+ years ago), the rule was simple; lacquer would go over lacquer only. Enamel will go over either, but lacquer is too hot to use over enamel without risking a lift.
If you want real good paint,never paint.... paint over paint. strip it and be glad later. If you are lazy it can be recoated and MIGHT...... never craze or flake off.....Good luck.
Absolutely,....Couldn't have said it better myself,...with the costs of refinishing materials today why screw around and take the risk?
One good day with a DA will take care of that lacquer and give you a good foundation to start building on. Always use a good sealer to eliminate any problems. Better to spend a little extra sealing the surface than risk problems when you are putting down color.
I Would Stripe The Old Laquer Off With Stripper Or A Da But Dont Paint Over It With A Urethane Catalized Paint.it Will Lift(wrinkle) The Laquer As If You Just Put Stripper On It.i Work In The Bodyshop Business And Have Been Around Laquers,trying To Seal Laquer Is A Bandaid That Will Come Off When The Sun Hits The Car.the Laquer Will Reflow And Cause The Topcoat To Crack/check.try Wiping Some Of The Basemaker Reducer Onto The Paint,it Should Just Melt It.thats What Will Happen When You Spray It.also The Primer-sealers Out There Need A Reducer To Spray It Before The Base.with The Price Of Paints I Would Stripe Whatever Surface The New Paint Will Be Put On.
One more peice of advice. I it was stripped to bare metal and the topped with lacquer primers and paint you might be far ahead to strip it again. If it's been sitting in a high humidity area it might by rusting under that lacquer. Laquer product are poris and do not provide a moisture barrier like new products like DP40 or equivilent. It might not be apparent now but it'd be the pits if it showed after the expence and work of repainting.
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