I ordered a few cases to be CNCd with powder coat for the top part, I will tell you if I’m satisfied with the finish.
Powder coating is not very commonly used on a keeb, maybe because the coating thickness is quite big compared to other techniques like anodizing or cerakote.
Coating thickness can vary greatly depending on the powder used and the talent of the applicator.
Too thick and you have the ‘orange peel’ problem.
Normally for a standard powder type with uniform color you’d expect between 2 to 4 mils of thickness, and your case dimensions must take that thickness into account to be able to assemble it.
But the finish is very durable and when you see what @norbauer is able to achieve with specialty powders it is definitely worth it and adds originality.
Another finish that I am interested with is the anodizing type III (called hard coat anodizing).
This finish is VERY durable and the coating thickness is also quite big (0.05mm on average).
But it is still less than powder coat as the oxyde layer grows equally under and on top of the piece so that it only adds 0.025mm thickess in reality.
As for coloring you have not much choice though, it is black brown or grey dye, or no dye at all (depending on aluminium, type III already gives a medium and/or brownish color to the metal).