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Q&As since 1989


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Brass Polishing Problem

Q. I am starting a small metal polishing business. I plan on polishing metal trim and draft beer towers located in restaurants and bars. Most of the metal is brass. What would be the best method of polishing brass?; what type of polishing compound?; will that compound damage bar tops or glass?; how often would polishing be recommended to maintain the shine? (bi-weekly, monthly); best way to first clean and polish heavily tarnished brass? Do you have any other advise I need to consider? Thank you for your time and help.

Steve Sheil
polishing shop, Long Island, New York
1999

A. There are a lot of variables to consider in your questions, Steve. First, the basic polishing process is pretty straight forward. I think ideally you might want to remove the tarnish and oxidation by chemical means; I'd use 50% Hydrochloric Acid. I have also had considerable success using very fine glass bead (#9) and removed the oxidation with blasting. The surface is then very easy to buff.

I'd use a pleated cotton buff to buff the brass with a brown tripoli rouge (polishing/buffing compound) [affil links] to do the "dirty work" and finish the color buffing with a chrome rouge or jeweler's rouge (polishing/buffing compound) [affil links] to obtain a high color bright brass finish. All of these materials are available with polishing and buffing distributors in your area.

The materials you'll be using will definitely scratch and damage glass and other surfaces so you need to have the pieces disassembled before you finish them. If you have to finish the items on site it proves to me much more difficult and time consuming.

You could get a flexible shaft polisher that will allow a sort of portable buffing wheel but they can be tricky to use in inexperienced hands. I have done jobs this way but I don't recommend it to the novice.

Unfortunately, the buffing is the easy part. A lot of people can buff, but not everyone knows how to maintain the luster of the buffed finish. This can only be done by applying a protective coating over the buffed finish which are innumerable in possibilities. You can use conventional acrylic lacquers, two-component polyurethanes, high solids baked enamels, clear powder, etc. I recommend that you talk to several paint manufacturers in your area to get advice on the most effective coating for your particular application.

If you don't protect the buffed finish, eventually you'll be right back where you started. There really isn't any way to predict how quickly that will occur either. It depends on several factors such as temperature, humidity and the general environment of the brass. Put a piece of brass on the Atlantic Ocean and it could tarnish in hours, put it in the Mohave Desert and it might take years.

Good luck with your endeavor. If you do it right, you could make a nice living with it.

Daryl Spindler, CEF
decorative nickel-chrome plating - Greenbrier, Tennessee
1999

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Q. One of my customer who is doing precision turn-part now facing a problem. Recently they are machining brass part so they need to wash away the cutting oil with hydrocarbon solvent. They dip the parts into hydrocarbon solvent and then spin. But after few days, they found the brass parts' surface do have rust- stain on the parts' surface. So, what should we do in order to prevent the Rust-stain? Please advise, thank you !

Chia Ming How
- Pekan Nanas, Johor, Malaysia.
2000

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Brass sheets surface defects after polishing

Q. Hi everyone
I am Arun from India; I am manufacturing brass utensils. On brass sheets I am getting some dot like marks, even after polishing the metal.

Arun Anand
- Chennaities, India
May 20, 2018