powder coating - before or after machining?
powder coating - before or after machining?
(OP)
Currently we powder coat our aluminum parts after machining. Some of the masked edges are rough looking. I was thinking of powder coating before machining but I don't know how well the powder coating will handle the rough handling in the shop. Also I worry about cleaning. Anyone out there powder coat and then machine your aluminum parts?





RE: powder coating - before or after machining?
But, I'd think that if you had rough edges before, you'd had rough edges after, and there's some possibility that you could get chipping, etc., from the machining operations, on top of whatever lubricants that you might use in machining will probably alter the appearance of the powder coat.
TTFN
RE: powder coating - before or after machining?
I would recommend machining first. Only do touch-up machining to remove overspray, provide sharp coating lines and expose electrical contact areas. Maybe can save $ not skipping the masking of difficult-to-mask areas.
Also, first take a painted part to your machinists, show them the rough paint edges, and ask how they would do it better & w/o hurting the paint. They can if they want to, so make it their decision as much as possible.
RE: powder coating - before or after machining?
What type of features are you trying to mask?
What machining operations would be involved? (Drilling, Milling, Turning, ???)
RE: powder coating - before or after machining?
An alternative method (as described before) is to remove the masking prior to curing the powder. This method often works best to avoid re-working the part and the sharp edges that can occur when masking goes through the cure cycle. In the worst case scenario, only minor machining is required, provided the masking operators are careful when removing the masking plugs.
A number of companies carry masking parts, including tapes and silicone molded parts. Many of them can design custom molded parts for unique masking situations as well, including us at www.viadon.com.
Hope that helps.