In this video You can see how to alter a jewel to preferred dimensions. Recently i ordered a jewel lot from Redrooster UK so i was choosing one with good external diameter and thickness.
0.17mm hole was drilled, oil cap was burnished and the flat side was polished. Ugly video but i hope You can find it usefull.
Another jewel altering adventure. The Nachtigall movement i am working on had an oval shaped roller jewel which i was breaking during repivoting. Yes, i should have removed the roller table but dont have the removing tool yet. It was no problem until the whole thing flown away from the pinion polishing tool. Used that for the first time and didnt hold the polishing file securely.
Back to the topic. I have measured/calculated the hole dimensions in the roller table on a microscope image. Lu