Summary for mil-std-171e finish numbers Discussion
CARC coating and MIL-STD-171 confusion comes from a paragraph number that looks like a finish number. Doug Paschall asked when to use revised MIL-STD-171E because a job called for finish 5.3.1.2 or 5.3.2.2, while a plater said zinc phosphate and the newer standard seemed to require CARC. The answer explains that the issue is resolved by Table V of MIL 171E, which lists finish numbers. According to the reply, Finish No. 5.3.1.2 is DOD-P-16232, now MIL-DTL-16232, and Finish No. 5.3.2.2 is Type Z zinc phosphate, Class 2, treated with MIL-C-16173, now MIL-PRF-16173. In other words, the cited finish numbers do not automatically mean CARC; they point to specific coating systems. The discussion emphasizes checking the finish-number table rather than assuming the paragraph number itself defines the coating.
Q. We are a 2 man job shop just getting started on military work and the paperwork is making me DIZZY! I saw a thread a while back on here about CARC coating but I had an additional question. We have a little job to quote that requires a final finish of 5.3.1.2 or 5.3.2.2 MIL 171. I talked to a plater and he said it was a zinc phosphate coating but MIL 171E states it requires CARC. When are you supposed to use the revised MIL-STD-171E? ASSIST doesn’t have the original 171. I hope I made sense. Thank you for all your help.
Doug Paschall
– Paris, Tennessee
2006
A. The confusion is from a paragraph number identical to a finish number. See Table V of MIL 171E for Finish Numbers.
Finish No. 5.3.1.2 is DOD-P-16232 [now MIL-DTL-16232 [from
DLA]
], Type M (Manganese phosphate), Class 2, treated with lubricating oil conforming to MIL-L-3150 [now MIL-PRF-3150 [from
DLA]].
Finish No. 5.3.2.2 is Type Z (Zinc phosphate), Class 2, treated with MIL-C-16173 [now MIL-PRF-16173 [⇦ this spec on DLA ] Grade 3 corrosion preventive (MIL-L-3150 oil allowed for very small parts).
The supplemental treatment product must be on the current respective QPL, either 16173 or 3150, available from ASSIST.
Generally, use current specifications in lieu of superseded ones. Note when doing so on the documentation. Occasionally, an unobtainable ECO or lack of a current equivalent necessitates using an obsolete finish to satisfy an old blueprint.
Ken Vlach [deceased]
– Goleta, California
Finishing.com honored Ken for his countless carefully researched responses. He passed away May 14, 2015.
Rest in peace, Ken. Thank you for your hard work which the finishing world, and we at finishing.com, continue to benefit from.
RFQ: NEED TO SETUP SMALL OPERATION IN-HOUSE TO APPLY DESERT TAN CARC FINISH TO ARMOR STEEL PRODUCTS THAT I AM TO MANUFACTURE FOR U.S.ARMY. NEED INSTRUCTIONS ON WHERE AND HOW TO START THIS OPERATION TO MIL SPEC.
J. SARLES
MFGR – DECATUR, Alabama
2007
Ed. note: This RFQ is outdated, but technical replies are welcome, and readers are encouraged to post their own RFQs. But no public commercial suggestions please ( huh? why?).