Troubleshooting "Craters" in Latex Acrylic

Finishers suggest possible causes for a cratering problem with sprayed latex acrylic. October 25, 2006

Has anyone tried spraying latex acrylic? We are trying to use this product and keep getting craters. Our finishing rep doesn't know what's causing it and the lab doesn't know either. We have also tried a couple other brands of latex acrylic and get the same results.

Forum Responses
(Finishing Forum)
From contributor M:
Are you coating over new or refinished woods?

From contributor C:
Possibly overthinning, as all water base finishes seem prone to fisheye faults when overthinned. Try raising the viscosity level.

From contributor J:
This is new work. We primed with QD30, which is a fast drying oil based primer and it sands really well. Anyway, two coats primer sanded well between coats. No, we didn't do any thinning... using airless sprayer.

From contributor K:
Been there, done that. I had to sand one down and shoot it with oil based enamel. I had used lacquer primer, but I don't think that had anything to do with it. My paint store did a draw down test, which is a bar with 6 mil bumps under it. They poured some paint on a test sheet and drug out a layer of paint 6 mils thick. It cratered on the test page also and that eliminated my primer, spray equipment, etc. The next one I do will be white lacquer all the way.

From contributor A:
The number one cause of fisheye in all wb finishes is zinc stereated sandpaper (anticlogging/nonloading). Switch to a plainer paper or buy some of Mirka's bulldog. Tack clothes are a big no-no as well.

From contributor M:
Another no-no is steel wool; use the nylon rubbing pads.