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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 The link with the information is: https://www.astm.org/cgi-bin/SoftCart.exe/DATABASE.CART/WITHDRAWN/A164.htm?E+mystore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.
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