Powdercoating a set of wheels for a friend in mirror black. Did the first one today and it came out beautiful. I left it in the oven to cool, but cracked the door open about 2 inches. Apparently that was open enough to let dust and pollen get in and ruin the finish. Stripping it again now. I guess I need to just leave the door closed for a couple hours after each one and do the slow cooldown.