Deft lacquer sprayed over latex paint?

[Roger Lueck]

Has anyone successfully sprayed Deft nitrocellulose lacquer over latex paint (white)?

Is any special preparation required, sanding with 320 grit or ???

Thank You,
Roger

[Jim Becker]

Don't do it. The solvents in lacquer will do very nasty things to other finishes.

You "can" use regular varnishes, both oil based and water borne, with the latter preferred. But do remember you're putting a "hard" finish over a "soft" finish (in most, but not all cases, with latex paint) so that has it's own challenges. If you need a harder colored finish, use a 100% acrylic product, especially if it's for things like shelving, etc., to avoid "blocking" (sticking) of things you put on the surface.

[Steve Schoene]

I'll second Jim's admonition. You would likely see the latex paint start bubbling off the surface.

[Roger Lueck]

First of all, Thank You to Jim and Steve for your replies. However, before I had the opportunity to read them, I contacted the Kelly-Moore Paint store from which I purchased the white latex paint and inquired about the possibility of spraying Deft nitrocellulose lacquer over their indoor/outdoor latex paint.

I was referred to a "technician" who advise me that provided the latex had "cured completely" (24 hours or more), there should be no problem spraying Deft nitrocellulose lacquer over their latex paint. This specific application of "lacquer over latex" was attractive as it appeared to potentially be a method to increase the durability of the finish as well as the ability to easily clean the object (it will be subjected to periodic handling).


I prepped the item I had previously sprayed with Kelly-Moore white latex paint and sprayed 3 coats of the Deft nitrocellulose lacquer. Ambient temperature was 75 - 78 degrees, humidity was approximately 65%. The Deft nitrocellulose lacquer (aka brushing lacquer) was not thinned and was sprayed with a HVLP gun. The first two coats were sprayed approximately 15 minutes apart with the last coat sprayed approximately 30 minutes after the second coat.

I finished spraying the Deft nitrocellulose lacquer over the Kelly-Moore latex white paint more than 5 hours ago and it worked, no problems whatsoever.

[Jason Roehl]

I would have tested this process first, but I'm not surprised by your results. The solvents in lacquers, though strong, tend to flash off VERY quickly (seconds), while even some of the strongest chemical strippers have to sit on latex/acrylic paints for a while (minutes) before they begin to work.

[Art Mann]

Lacquer thinner is not a very effective stripping agent for Latex paint. I know because I tried it once. I will say that the story might not be over yet. A day or two really isn't enough for me to be confident of the compatibility of the two materials. We will just hope for the best.

[Jason Roehl]

Lacquer thinner is not a very effective stripping agent for Latex paint. I know because I tried it once. I will say that the story might not be over yet. A day or two really isn't enough for me to be confident of the compatibility of the two materials. We will just hope for the best.

I've used lacquer thinner quite a bit to clean up latex paint "oopsies" over the years. I just get some on a rag and hold it over a latex paint drip or overspray for a few seconds, then wipe it away. Because the solvent flashes off so quick, it's not as likely to damage anything underneath. After a day or two, I doubt there's ANY solvent left in that film of lacquer that could be attacking the paint (probably true after a few hours, if not minutes).

[Art Mann]

When I'm talking about stripping paint, what I mean is removing the latex paint from a piece of (what would be) nice antique hardwood furniture that has been defaced by some well meaning do-it-yourselfer. Lacquer thinner readily dissolves dried lacquer or shellac but it just sits there and evaporates on dried latex. I'm thinking that is more like the situation of the OP. I have refinished a lot of furniture and I have seen some strange things happen when various solvent based materials were combined with water based materials, even if it looked fine to start with. So far, it has only been one day for the OP. I would not feel really good until a few more days passed by.

[Roger Lueck]

24 hours have elapsed and the finish is looking finer than frog's hair. From past experience using lacquer based automotive paint, after 24 hours, depending upon temperature and humidity, there is less than 6% of the carrier (thinner) remaining in the finish, therefore the finish should be stable. After 48 hours the amount of carrier (thinner) remaining in the finish is less than 3%, however it may be 21 - 30 days before the lacquer is cured enough to be wet sanded and buffed depending on the number of coats applied.

For the sake of argument, I will enter a final post tomorrow evening documenting the condition of the finish 48 hours after application.

[Roger Lueck]

I understand this a lengthy amount of time for a final analysis, however after over 1 year and 6 months, the original item I sprayed has had no problems and subsequent items I have used the same method have not experienced any problems wither to date.

[Wayne Lomman]

Roger, it breaks all the rules but it has worked. My first reaction was the same as Jim's incidentally. Cheers