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How red is "red" anodize for MIL-A-8625, type 2, class 2?

What amount of variation to the color "red" is allowable that meet the spec? Our customer's requirements is red anodize per MIL-A-8625 / MIL-PRF-8625 [on DLA], type 2, class 2. The mil-spec talks about uniformity being specified by procurement, but is that the same thing? Until the last lot, our supplier was sending parts that were undeniably "red". But the last lot is a light shade of rust - much different. Is that variance in color normal for the process?

Ron Corkle
buyer - Joplin, Missouri, USA
2007

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First of two simultaneous responses --

Have a conversation with your anodizer. His shop let something get out of control. Your PO should have specified the color in reference to a Chip or a previous part that has been identified as a "standard" or "acceptable". To really cover yourself, you need an unacceptable part that is too light and one that is too dark. Without the "boiler plate", you are going to have to negotiate or arbitrate a solution, which may be another anodizer.

James Watts
- Navarre, Florida
2007

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Second of two simultaneous responses --

Ron

Without going into the requirements of the specification, there are a number of process variables that will effect the intensity and shade of dyed colors.

A sensible approach to determining acceptance criteria would be to have your supplier produce a number of samples that vary in color from light to dark. Pick 2 and cut them in half. The anodizer gets a set and you get a set. There should be minimal questions about whether future parts are acceptable.

Be advised that the closer the two samples you choose are to one another, the more you should expect to pay!

Willie Alexander
- Colorado Springs, Colorado
2007

There is no red that is specified in the MIL-A-8625F Standard. If you have provided your supplier a color sample, then this is what they would,and should go by. If the color range is that drastic, it would seem that there would be grounds for discussion on reworking the material if dimensional tolerances allow.

Michael Hancock
- Indianapolis, IN, USA
2007

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All the other response are right on target. Since you are doing Mil-spec work, it is also important for you to involve your internal quality and your customer as to what is (arbitrarily) acceptable, since "red" is ambiguous and you don't want them rejected on your customer's dock. Unless, you have design authority, in which case the "call" is your engineering department.

Douglas Hahn
- Saint Charles, Missouri
2007