Just took apart my 60s Slingy snare for a good cleaning. It's a COB gold/black badge serial # 229670 with 3 lines - Sound King? When I cleaned the inside with a dry cloth the cloth turned gray as the finish rubs off. Should I just leave it alone or use a metal polish?
Every time I shine ANY chrome be it wheels, drums, kitchen faucets etc. the rag turns a grayish black color. I have the same snare you have and didnt see any damage after I cleaned 'er up. Wait for an old timer to ring in on this to be sure as I have only cleaned one snare, ever, but I think the discoloring of the rag is pretty standard when cleaning chrome.
have a wonderful evening
drumhackx-mas3x-mas1:Snow Flake:x-mas2