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Is "timesaving" of aluminum sheet necessary for a clear chromate finish?

I am a mfg eng. Our customer specs call for clear chromate finish on aluminum sheet parts. We time-save all aluminum sheet. I am trying to determine if there is a good reason we do this and if it is necessary. Otherwise, I would like to stop doing it to reduce the cost of producing these parts. The parts do not require a timesaved look. I am being told that the clear chromate will not adhere to raw aluminum sheet unless it is "roughed up". Is this accurate? Thank you.

Brad Goldman
engineer - Austin, Texas, USA
February 24, 2011

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Yellow and Clear chromate will "stick to" (properly adhere) to any aluminum surface that has been cleaned and deoxidized. We prefer NOT to "time save" because most machine shops that have Time Savers go back and forth between steel and aluminum, then they imbed iron particles into the soft "Kleenex-like" aluminum, subsequently imbedded iron particles set up corrosion sites and defeat the purpose of chromating.

Robert H Probert
Robert H Probert Technical Services

Garner, North Carolina

February 25, 2011