“I recently purchased a paint spray booth. I paid an extra $1600 to it have powder coated. While I was putting it together, I noticed some runs in the coating. Also when I tried to wipe off some paint splatter with thinner, the coating turned soft.
I was under the impression that powder coating was very strong and tough. Was I wrong or is this correct? I am trying to determine if I paid for something I did not get. I would appreciate any information you can provide as I don’t have very much knowledge about powder coating.”
“Most powder coatings do not run (or sag) easily. This doesn’t mean they can’t run. If they run the coating thickness is above 25 mils (0.025 inches). That’s a pretty thick coating. However, liquid paint can run fairly easily even at a thickness that is under 2 mils (0.002 inches). Therefore, you should check the paint thickness and surface appearance (since most powder coatings applied in thick layers will have more orange peel than liquid coatings). If the coating is relatively smooth and thin, then your paint booth was coated in liquid. If the coating has a lot of orange peel and is thick, then it is probably a poor powder coating.
As for wiping the coating with solvent, this doesn’t prove much since some powder coatings can’t take that abuse, even if the coating was properly applied. Even the best powder coatings will soften with solvent if they are not fully cured. This is in fact the test used to determine cure (using either MEK or a MEK/Xylene mixture). Bottom line, you need to do more investigation before you accuse your supplier of wrongdoing.”