HELP: another novice screw up with lacquer

[Zahid Naqvi]

Ok so I am re-finishing a table with lacquer(brushing) over a spray paint (American Accents spray can from HD). I have applied three coats on the first table top without any problems. But as soon as I try it on the second table this happens.
Appologies for the quality of the pictures, but I took several shots and this was the best my digi cam could do. What the heck happened here.

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The paint sorta cracked and flaked, the cracks look like a dry lake bed which hasn't seen rain in ages.

[Steve Clardy]

How long did the paint dry before applying lacquer?

[Zahid Naqvi]

How long did the paint dry before applying lacquer?

It's been drying overnight. But this is the same piece I had asked about regarding a pre-existing lacquer coat. I didn't remove it completely, sanded it to get a rough surface, painted it overr followed by this lacquer coat. I am thinking the paint didn't grip the underlying lacquer strong enough. But then again what do I know about these things.:mad:

[Wes Bischel]

Zahid,

I think Steve has hit on the problem. The original finishes need to cure/offgas. Check the directions on the paint and laquer - some need to recoat with-in an hour or so, or wait 5-7 days. DAMHIKT:rolleyes:

Wes

[Steve Clardy]

Spray can paint off the shelf may dry, but doesn't harden up for several days, maybe even weeks.
So I think that the lacquer, which burns in, burnt into the paint which wasn't cured.

[Brad Olson]

You also should always prime when refinishing. You'll never get good results going over an old finish without priming.

You want a primer specifically designed to stick to old scuff sanded finishes.

Paint just doesn't stick well enough to go over an old finish.

Also as mentioned above, the lacquer thinner in the lacquer dissolved the the poorly bonded and not fully cured paint.

[Zahid Naqvi]

So I guess I have to take it all off down to the wood and start all over again.:(

[Brad Olson]

My recommendation would be to strip and start over.

Stripping with a Methylene chloride based stripper isn't much fun, but works very well and is relatively quick. Just wear a respirator and recognize the flamibilty hazards of the stripper

Give the piece a light sanding to even everything up and then prime, paint, allow paint to fully cure (rule of thumb would be 7-10 days) then coat with lacquer on top.

If you are painting with oil based paints, I see no reason to use a lacquer top coat. Most oil based paints are pretty tough once they cure. If you are trying to get a hard clear coat to protect the paint, I'd consider a pre-catalyzed lacquer in stead of regular lacquer. Another option would be a water based poly that will cure clear. Oil based poly is an option but it will yellow a bit.

[Steve Schoene]

Your earlier question was about paint over lacquer, if I remember correctly. That will generally work fine because the lacquer isn't susceptible to the relatively mild solvents in most paints. But lacquer thinner is rather more potent and may actually be a solvent for the paint resins, even when dried, especially if not fully cured. Consequently paint over lacquer may work when lacquer over paint doesn't.

[Zahid Naqvi]

you guys are great. I love this internet thing, how did people work before Internet.

[Dennis Peacock]

Oooohhhhhh. Hey Zahid, I learned that lesson about 3 years ago on the LOML Jr's iron bed. The paint has GOT to be dry and "hard". I found that it took the stuff I was working with about 5 days to be cured enough to topcoat with lacquer.

Lesson learned the hard way.:o :rolleyes:

[Sonny Porter]

Sometimes if there's a compatibility problem, a spit coat of shellac can act as a barrier between finishes. This would mean spraying a thin coat of denatured alcohol and shellac, in a 5-6 to 1 ratio. 5-6 parts denatured alcohol to one part shellace.

By spraying it on, you can even use shellac on top of a finish which it might otherwise dissolve.

[Howard Acheson]

You have run into a compatability problem. The solvents/thinners in the lacquer overcoat has destroyed the the paint underneath. I'm not sure what American Accents is, but the solvents in lacquer will "eat" into new oil based finishes and any waterborne finish.

You will have to strip off the finish completely and start over. If you still want to used the American Accents, either use it as is with no overcoat--why did you want to overcoat it anyway?--or use a clear overcoat made to be compatable with the American Accents.