Hi I need to draw some basic designs for some gem centring tools for gem cutting (faceting). My idea is to modify a 4 jaw and a 3 jaw self centring lathe chucks. I don't know if they make a four jaw self centring chuck similar to the three jaw chucks, but this is what i'd like.
I'm not drawing an engineering design but a drawing to display the concept of what i want made. While the main section of the jaw is adjusted by the centring screw thread, two opposing jaws will have a top section that will have an adjustments of about 5 cm each. To ensure a reasonable accuracy the two adjustable jaws will have calibrations engraved on their sides.
The back of the chuck will be closed with a removeable die, which will have a whole for a rod (dop or dopstick) which the uncut gem will be adhered to, once centred.
The three jaw chuck would have a similar configuration.
Kevin