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Zinc Plating Specification ASTM A164

2006

Plating spec. question: what is the below plating definition?
ZINC PLATE PER ASTM A164 TYPE RS OR EQUIVALENT

plating thickness? any Chromate coloring? Is it commercial?

Fred Barry II
fastener mfg. - Worcester, Massachusetts

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Sorry, never heard of it. I don't claim to have heard of everything, of course, but if no one gives a more positive response either, perhaps there is a typo in the spec number.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2006

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An internet search quickly determined that in 1981 this spec was canceled and replaced with the current ASTM B633. The link with the information is: https://www.astm.org/cgi-bin/SoftCart.exe/DATABASE.CART/WITHDRAWN/A164.htm?E+mystore

Milt Stevenson, Jr.
Syracuse, New York
2006

ASTM A164 is not a current specification was replaced in 1985 by ASTM B633. I believe that type RS was the thinnest of the specified zinc coatings and was approximately .00015 inches. The other thicknesses were type LS and GS. I think chromate was addressed in another part of the spec.

John C Williams
Nutec Metal Finishing - Birmingham, Alabama
2006

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2006

Several reference books confirm John's thickness info for ASTM A164-40T, -49, -55:
"The minimum thicknesses on significant surfaces...are
"G.S.," 0.025 mm (0.0010 in.);
"L.S.," 0.013 mm (0.0005 in);
"R.S.," 0.0038 mm (0.00015 in.).
...The "R.S." coatings are suitable only for indoor or temporary use."
-- Modern Electroplating, Allen G. Gray (ed.), p. 457 (1953).

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.