I’m getting started, and am coating an aluminum enclosure. It’s fairly thin, about 18 guage aluminum, as you can see in the attached pics.
I have the Eastwood Hot Powder Coat system, and I’m using Eastwood PC, the “vermillion” color. After three tries, with sandblast/pre-heat prep all three times, I’m getting the same problem: part of the PC appears to bake-off during curing. I am following the recommended practice: pre-heat to 450, put the coated part in until it completely flows out, cure for 20 minutes at 400. I have tried light coating, heavy coating, pre-heating the part and shooting it cold — in all cases I have this problem.
In the attached pics, you can see where part of the surface has a good, vermillion-colored coating. The other part of the surface is lighter, this is the problem. On the lighter-colored area, after curing, there is a very fine “dust” that can be wiped off, although wiping it off doesn’t appear to change the color.
My first guess is that the part is too close to the elements in my curing oven, or the elements come on too hot and create a localized problem just near the elements, even though the overall temperature in the oven is still only 450/400. But, maybe it’s something completely different.