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Brass Polishing and Coating

2006

I am looking for an inexpensive way of polishing and then coating brass parts so they will not tarnish, specifically brass tubing approximately 8 inches long with a diameter of 1.75 inches. These parts will be used for a decorative lock box and the brass tube will slide in and out of a larger aluminum tube.

I do have smaller brass parts that would need similar processing, but the tubes are my main concern due to their size.

I am wondering if it would be less expensive to tumble polish these tubes or would it be better to hand buff them. The quantities I have would be in the several hundreds (possibly thousands) and hand buffing may be too expensive and/or time consuming. Any other suggestions for polishing (acid bath, electrostatic, etc.) would be greatly appreciated.

I have considered plating, but it is important to maintain the brass color of the metal and plating may be too expensive.

I am not certain if it would be possible to tumble polish parts of this size, but this would seem to be less labor intensive than hand buffing. Hand buffing might be alright if I had 50 or so parts but 500, 1000, or even 10,000 parts may be way to many to hand buff on a buffing wheel.

Once the tubes are polished, I will need to coat them in some way to keep them from tarnishing. I have considered Powder Coating but this would add too much to the diameter and has a tendency to scuff (when slid in and out of the larger aluminum tube).

The level of polish does not need to be a mirror finish, but should be enough to shine similar to sanding with 600 grit sandpaper (in small quantities thus far I have used this method by placing the part on a lathe and wet sanding the brass to get a suitable polish ù also too labor intensive and time consuming).

The coating I have been using is air brushing the parts with a pigment free Polane paint, but this has a tendency to scratch off after a while. I would be very interested in learning about another cost effective method of coating brass that could be done in large batches and which will not add too much to the diameter.

The main concern is to get an inexpensive, yet reasonable polish and finish on these parts as hand buffing and air brushing parts may be too expensive and very time consuming to do in very large quantities.

I am looking to outsource this work so if you have a suggestion of someone who would be able to do this in my area (Western Washington), this information would also be appreciated. But information on a process or method would also be acceptable as I could then search my area for someone who could do this.

Thank you very much for your time and any suggestions you might have.

Justin Nevins
- Tacoma, Washington, USA

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2006

Can't help you with the coating problem, but you should resolve it before you decide on your surface finish on the tubes. Meaning, I think you will have problems with any finish if your part is going to slide within a mating part. Kind of like why bother, because the appearance will constantly change due to friction.
If you figure out that problem, I can say that mass finishing is a good candidate for burnishing/polish your tubes.

AF Kenton
retired business owner - Hatboro, Pennsylvania