In Reply to Parent Post by Phil Fields
I have a question concerning anodized aluminum. Historically I have not had quality issues concerning the anodized aluminum parts that we purchase (made to company print). Recently we have been experiencing stains, raised surfaces, surfaces imperfections, etc.
Is there a standard/preferred surface preparation that should be performed prior to the anodize process?
I'm not an expert at anodizing, but have put a lot of time into dealing with anodizing issues over the last few months...
Sounds like your anodizer might be using a dirty bath and contaminent is getting in. Or perhaps he's not cleaning the parts properly prior to hitting the anodizing tub. We send our parts with a left over coating of cutting oil that the anodizer cleans them off in an ultrasonic bath.
We typically see "staining" in parts where condensation may sit after the dye bath. It appears as discolored spots.
We've also seen surface imperfections from dirt that didn't get cleaned off the part.
I'm not sure by what you mean by "raised surfaces"...