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Polished Brass Plaques

2007

I have a client that would like a 12" x 40" plaque polished with no visible grain. It is a corporate identification plaque. Aesthetics is everything.

Traditionally we use a bench grinder with a polishing wheel and jeweler's rouge (polishing/buffing compound) [affil links] to polish however this plaque is quite large and is 3/8" thick. Its very heavy. I'm wondering if there is another type of machine that would polish a plaque like this or even if there is a chemical polishing process that could be used.

Jon Lorber
precision engraving - Amityville, New York

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First of two simultaneous responses --

Plastic injection molds for transparent parts and other plastic components are normally polished to a mirror finish by use of hand held rotary tools with mounted felt bobs and polishing diamond compounds. Their shapes are usually very intricate and they normally are much bigger than your plate, so you must be able to do it this way. Another option would be a chemical bright dip but the finish may be a little disappointing.

Guillermo Marrufo
Monterrey, NL, Mexico
2007

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Second of two simultaneous responses --

Unless you're buying previous super #8 before the plaque was made there's really not a whole lot you can do, do you have an employee that is highly skilled in using a manual buffer, there are ways to blend it in in order to make the grain not as distinctive but you can't eliminate the grain.

Brandt Hinton
- Elk River, MN, USA
2007

Mold polishers are used to polishing to mirror heavy parts with intricate shapes using hand held rotary tools and abrasive pastes.

Guillermo Marrufo
Monterrey, NL, Mexico
2007

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2007

Zicronium brass (PVD) stainless in True #8 mirror finish should have been used. No polishing needed... ever, no lines ... ever.
Perfect application. End of story.

Michael Liu Taylor
specialty stainless steel distributor - Dallas, Texas

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Zirconium PVD stainless is a possibility to be considered, Michael, and we thank you for it. But "end of story" may be a bit dramatic when we don't yet know what other metals, if any, it must be compatible with, and the subject of engraving of the plaque hasn't yet been broached yet :-)

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2007

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Zicronium PVD coating on stainless is usually applied on stainless steel sheets with a maxium of 3.0mm thickness, 11GA or 1/8. Didn't noticed the post had a plaque of 3/8" thickness.

Maybe the simple solution would be to laminated to a substrate.
As to engraving it, there's no problem. Diamond engraving.
On a recent project, we had 11GA True #8 mirror finish stainless deep engraved and then color filled. :-)

Michael Liu Taylor
specialty stainless steel distributor - Dallas, Texas
2007