I needed to make some special hangers for a suspension display I am working on. I removed the pins from several dozen damaged discs that I had in order to get enough that were the same shape. Two on left came from 10 inch OB porcelain. (For comparison, Two pins on the right are from a 6 inch bell and the top part of a pin from a 12 inch heavy duty porcelain disc.) The pins in the middle are a mixture from 10 inch glass discs Sediver, EIV, LEV . A 9 inch Pyrex produced the pin with 3 ridged top.

It took a few removals before I got the knack. What initially took several minutes and much effort was soon much easier and mere seconds.