Home /
Search 🔍
the Site
pub Where the world gathers for
plating, anodizing, & finishing Q&As since 1989

"Tin/Zinc Plating with Black Chromate Treatment"



I received a military print for a small plain carbon steel, stamped part. The part will be heat treated to 32-40 HRC and the print calls for Tin/Zinc plating per WSE-M1P93-A1 with black chromate treatment. My Tin/Zinc plating company out of Chicago claims a black chromate treatment to a Tin/Zinc plating is impossible (or at least not done). Is this true? Any help would be appreciated.


Ryan Nelson
- Oklahoma City, Oklahoma


Tin-Zinc with a black chromate is not normally done. There are some chromate products just released to the market that we will be testing in our lab very soon. We also have some tricks that can produce Tin-Zinc black now.

Andy Scheer
- Pacoima, California, USA


Tin-Zinc colors currently are yellow and white (clear). Any black, green or whatever is not possible with one exception:

Some people want their finish of tin-zinc to look as nice as regular zinc. What some platers are doing is to "strike" or "flash" a coating of traditional zinc over the tin-zinc. Then they apply a regular zinc chromate of yellow, blue (or whatever) on top of the zinc strike.

Now, the product has the protective coating of tin-zinc, with a very fine layer of traditional zinc, followed by a traditional zinc chromate conversion coating with the color or their choice. The green or O.D. dye color could also be added on top of the zinc strike plating.

The downfall to this is two issues. One, cost goes up even more with a zinc strike applied. Issue #2 is that if one is following a tin-zinc spec (like Ford's for instance), adding the zinc strike coating on top of the tin-zinc may bring the plating job out of spec. It may also add other problems which are too long to get into here on this forum.

Roger Fasting
- Sacramento, California, USA

finishing.com is made possible by ...
this text gets replaced with bannerText
spacer gets replaced with bannerImages

(No "dead threads" here! If this page isn't currently on the Hotline your Q, A, or Comment will restore it)

Q, A, or Comment on THIS thread -or- Start a NEW Thread

Disclaimer: It's not possible to fully diagnose a finishing problem or the hazards of an operation via these pages. All information presented is for general reference and does not represent a professional opinion nor the policy of an author's employer. The internet is largely anonymous & unvetted; some names may be fictitious and some recommendations might be harmful.

If you are seeking a product or service related to metal finishing, please check these Directories:

Chemicals &
Consult'g, Train'g
& Software

About/Contact    -    Privacy Policy    -    ©1995-2023 finishing.com, Pine Beach, New Jersey, USA