I am currently in the process of re-organizing my abrasives and polishing compounds, so when Marcus mentioned the tedium of polishing his silver casts, my mind juped to this.
I have used this method once for buffing up the handguard for the rondel dagger when it was already mounted, so today just as further proof of concept of a procedure for buffing small parts that are difficult or impossible to do on the buffer due to complex gometry (or safety).
This is what I started with – an old rotary toothbrush head that I have saved up for this purpose specifically, an extremely old and corroded mirror holder (probably chrome-coated brass or something like that), a piece of never polished brass with patina (a waste piece from machining) and hard, coarse polishing compound. A bit too hard, this is a high-speed compound, a paste would be better, but I could not find it. Not pictured here are paper towels that I have used to wipe the polishing compound off of the piece after work and the green scrubbing pad (see further).
The corrosion on the mirror holder was extremely hard and resistant, so I had to use a piece of scrubbing pad too – but I only used it on the left (thicker) half of the part in the following picture, not the right, thin part so some of the pitting from the corrosion is still visible there. A big improvement over the initial state nevertheless.
On the brass cylinder, I did not use anything else than the toothbrush and polishing compound
It is hard to take pictures of the results, but in the end, I found a way – I think you can see which side is the unbuffed part of the brass cylinder, and which the buffed part. The time it took me was about 5 minutes, but it would be mere seconds on the buffer. Nevertheless, the biggest obstacle to using this on a bigger scale is the battery capacity of the toothbrush, but it could be useful for getting into nooks and crannies on small thingies.
©Charly, all rights reserved, click for full size.