I soak my larger metal parts in a tub of evaporust from www.theruststore.com. I soak it for 8 to 24 hours depending on the amount of rust, then rinse with water, then dry with a towel and use an air compressor to make sure all the water is pushed out. then I put a light coat of Boeshield T-9 by spraying onto an old t-shirt then wiping on the metal parts.
I have had pretty good results cleaning the dull metal ashtrays using a combination of steel wool (start with #1, then #00, then #0000), wire brush and buffing wheel on a Dremmel, and Blue Magic Metal Polish. I spend, on average, 1-2 hours on just the ashtray, as it take a huge amount of elbow grease to get a shine on that cheap, lead-based metal.
That being said, you could probably apply the same ideas to the ball tray. Just be careful when using a rotary tool on a surface that large. If you aren’t careful you will end up with permanant swirls in the finish. I would try the steel wool and metal polish first and only use the rotarty tool as a very last resort. Be patient and plan 2-3 hours to get that metal shined up. It takes time and patience, but should eventually shine.
P.S. – make sure you use gloves when handling the steel wool. I rubbed the skin off my fingers the first time I used the wool and was hating life for nearly a week.
Anyway an old timer gunsmith told me a trick about removing rust and crud from inside barrels. All you do is take a pocket knife and make some slits/cut marks perpendicular to the long axis of a wooden dowel. Then wrap 0000 steel wool around that and chuck the other end of the dowel in a drill and polish away.
I do a similar version now except I use a flex shaft on my dremel and it works like a charm. 0000 steel wool is my first choice for any kind of metal polishing on larger pieces or things that won’t fit in my tumbler.
Amazon.com: 4 3/8 X 5 1/2 Synthetic Steel Woll Pad (Super Fine): Home Improvement
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