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COLOR CODING OF METAL THAT DOES NOT ADD THICKNESS

September 22, 2009

Thank you in advance for looking at my question. We have a job that is a simple larger size washer that comes in many thicknesses all made to a strict thickness tolerance. We have been asked to "color code" the washers with each thickness having its own color. 15 different colors! Quantities range from 400 to 5,000 of each per run. We have attempted to dye the parts with limited success. Do you have another suggestion that we could look into that would be cost effective and not add any thickness to the part? This has frustrated us for sometime now and hope you can help. We are also ISO 14001 and have environmental issues to deal with.

Regards,

Tom Bader

Thomas Bader
Owner metal stamping company - Akron, Ohio, USA

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There are hundreds of company's that sell indelible inks like the ones used in magic markers. Some are even oil and solvent resistant and I really doubt that you could even measure their thickness with a common caliper. This is one such company. markem-imaje

Rod Henrickson
gunsmith - Edmonton, Alberta, Canada
September 26, 2009

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First of two simultaneous responses --

Are the tolerances tight on the faces only? How thick are the washers, i.e., could you color code just the rims?

Jim Treglio - scwineryreview.com
PVD Consultant & Wine Lover
San Diego, California

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Second of two simultaneous responses --

If washer thickness is the main concern paint the O.D. or I.D. or both. Use the most suitable ink for your purpose regardless of its thickness. Another option would be to lightly acid etch or sandblast every part through a stencil. These opertions do not produce raised bumps. G. Marrufo-Mexico

Guillermo Marrufo
Monterrey, NL, Mexico
September 28, 2009
September 28, 2009