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Dry Spray Diagnosis
Question
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From contributor P: That's an excellent example of dry spray. The finish is drying before it hits the surface, which causes the very coarse texture and white colored dust. Usually reducing the atomization air pressure is the first step to fix the problem. Thinning the finish and adding a little retarder is the next step. Try thinning the lacquer a total of about 10 - 15%; 10% regular thinner and 3-5% retarder (e.g., butyl cellosolve or MAK). I generally keep the retarder content at 3% max. If you're using Campbell's Care retarder, you may need as much as 10%. I haven't looked up the contents for their retarder, but on the few occasions I used it, I noticed small quantities weren't as effective as butyl cellosolve or MAK. From contributor D: It doesn't look like dry spray to me. It looks like there's a recoat window problem. Your subsequent coats of finish are causing the finish underneath to wrinkle. To see if you have a defective batch of finish, lay some out on a sheet of glass. Let it flash and cure a little, maybe 40 minutes. Then, do it again and see what happens. If you use two sheets of glass as your test substrates, apply one test by spraying and the other one by brushing. If your brush method lays out fine, then maybe my recoat observation is in error and it is an overspray problem. Better that I should be in error than you barking up a wrong tree.
From contributor M: I'm thinking you should ask the guy who prepared it how much catalyst he used. He is the only part of your equation that is different. From contributor P: Wrinkling looks very different than the picture above. The finish actually has wrinkles in it. It often occurs when a second coat of catalyzed finish is applied over an un-catalyzed sealer or primer. In this picture, it occurred when a pre-catalyzed pigmented lacquer was applied over an existing paint of unknown chemistry.  Click here for higher quality, full size image Dry spray produces tiny pebbles in the surface of the finish just like the texture in the photo. I have my own example, shown below, using a white pigmented lacquer. I like the questioner's example better.  Click here for higher quality, full size image From contributor J: Somebody already suggested this but I just thought I would back him up so you don't go on a goose chase. Same problem as you're having. Solution.... much more thinner and a touch of retarder. They say that you don't have to thin the product from can consistency, some even say don't, but I find most pre-cats almost unsprayable without at least a 2-1 mixture. From contributor N: 2 to 1 is excessive. 15% with lacquer thinner is about right. The retarder of choice is MAK and 5% will get the job done. Butyl cellosolve stays in the film forever whereas MAK releases very quickly. PM Acetate, IBIB, or Eastman EEP also work very well without the problems associated with butyl cellosolve. Trust me, I know all about slowing the flash off of coatings as I live in hell (aka Phoenix, AZ) and when it's 115F outside, you've got to make adjustments. From contributor D: I'm not ready to stand corrected yet. Soon, maybe. I still think that it's a recoat issue and not overspray. The finish did something. It may not have wrinkled, but the picture looks like the finish reacted badly with its undercoat, the previous coat of finish. If you're walking down the street and a person passes you by and tells you that you're drunk even though you never drink, ignore him. Ignore the next person who tells you the same bit of silliness. But Ed Koch, the former emperor of New York City, advises that if a third person tells you that you're drunk, lie down in the gutter. So far, I'm outnumbered here, stubborn as I am. Would you like to add information to this article? Interested in writing or submitting an article? Have a question about this article? Have you reviewed the related Knowledge Base areas below? 
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