This presentation details the process utilizing Stuller's innovative Preform Ring Sizing System. Stuller recommends that the drill press be mounted onto a flat surface in an upright position.  In this demonstration we are mounting a drill press onto a standard workbench.  The first step after mounting is to assemble the flex shaft onto the drill press by sliding the handpiece through the hole at the top of the press.  Then secure the handpiece by tightening the allen screw located in the back of the press.  Using a caliber, measure the thickness of the shank where the sizing joint will be.  This example illustrates a piece that measures a thickness of 1.25 millimeter.  It is now necessary to select the proper end mill bit according to the thickness of the ring shank.

Once selected, place into the handpiece. Place the ring on the drill press mandrel with the bottom center of the shank lined up with the groove in the mandrel.  Secure the ring in the vice by slowly tightening the ring using the small knob located in the front of the drill press. To assure the end mill bit is centered on the lap area of the shank before drilling, turn the large knob located in the back of the drill press. Make sure the bottom knob is tight and secure before proceeding to drill into the shank.  This assures that the manual assembly remains in place. Using a large knob on the side of the press slowly drill the lap area until the end mill bit goes through the ring creating the half moon effect on each end that will match the ends of the preform stock.  Following this, open the ring on the mandrel to the ring size required. In this demonstration we are sizing up one and a half sizes.

 It is now time to select the proper preform pre-cut sizing stock that is needed for your ring sizing job.  Note that the jeweler has selected a two-millimeter pre-cut preform piece.  You can now easily snap the preform piece into place.  Following the placement of the preform piece, the ring is now ready for soldering and other finishing processes.