I have been asked by a few people to put together a step by step pictorial guide to making a tapered collet for a faceted stone.
This is the way I do it and so far it has proved to work fine.
All pictures will enlarge if clicked for clearer viewing.
Take your compasses and set them to the distance between the two ends of the top line Pic11
Phew nearly done. Now make a line between the point at which the blue line intersects the outer circle to the bottom point where the two red lines cross. Pic17 marked in green,
Pic19 shows the part that will be the collet marked yellow.