Interesting tail weight.
This is near the exact system I have used for turning and finishing pins on miniature, single throw model engines. Works well and with a Spin Index fixture and a surface grinder you can also grind the pin!
Probably very similar to what the SAITO factory does.
I do not use "thumb pads" for final polishing like this. I prefer a shaped ,halfround wood or nylon block and a bit of 3000 grit "Micromesh®" diamond grit cloth.