Equipment and Supplies Required
- Bearing cutter burs (156 c) of appropriate size of the stones to be used
- Shor Ring Drilling Quadrant
- Drill press
- Shor ring collets (size of the collets to be determined by the size of the rings to be channel cut)
- Brass ring blanks (optional)
Setup
- Insert a bur of the appropriate size into your drill press chuck.
- Put a brass ring blank on a ring collet of the appropriate size and slip that collet onto the expanding mandrel of the quadrant. Be sure to push the collet all the way back on to the mandrel. Using a brass ring (instead of gold) will give you the opportunity of aligning your quadrant without the possibility of damaging a gold ring if you make a mistake.
- Tighten the expanding mandrel by turning the expansion knob slightly in a counter-clockwise direction. Never tighten this knob unless there is a collet and ring on the mandrel (that can damage the expanding mandrel). The collet may be loosened by simultaneously pressing down on the black plastic indexing knob and turning the expansion knob in a clockwise direction.
- Your quadrant come complete with 4 alignment bolts (packed separately). Screw these bolts into the 4 holes on the underside of the quadrant. The purpose of these bolts is to adjust the quadrant back and forth by length and width.
- Mount the quadrant on your drill press so that the ring is exactly centered under the point of the bur. We recommend mounting on a 1/8" sheet of metal by means of epoxy. The sheet can then be drilled for mounting on your drill press. By mounting in this manner, the press can easily be removed and remounted without the necessity of realigning the quadrant.
- Once mounted, aligned the ring (by means of the alignment bolts) at the exact point at which you want to begin channel cutting. Once aligned, it is not necessary to realign the quadrant unless you want to change the size of the ring that you are channel cutting or the position of the channel cut on the ring.
- Your quadrant is equipped with a 180 toothed gear. That means that you can index your spacing around the ring up to 180 times or any divisor of 180. This means that you can channel cut any distance on the ring within 2 degrees of arc (1/180th of the ring's circumference) or drill up to 180 evenly spaced holes around the ring.
- Each time, when you press down on the indexing knob and it clicks, you have turned the ring 1/180th of its circumference. You can adjust the number of clicks for each press of the indexing knob by raising or lowering the indexing stop adjustment screw. This screw has a locking nut which should be used to insure that the placement of the screw does not inadvertently change. By adjusting the screw, you can choose from 1 to 4 clicks (2-8 degrees of arc) per press on the knob. If you should want to use the quadrant without the indexing feature, simply remove the indexing spring. We strongly recommend that you set the stop adjustment screw for only 1 click when cutting channels. This allows for a much better controlled cutting rate.
Operation
- Determine how many clicks you want the indexing knob to give on each pressing and adjust the stop adjustment screw accordingly. Determine how far you want the ring to turn. determine either by experiment or by calculation how many pressings on the indexing knob this will require. Write down this number.
- Determine how deep you need to drill, drill the hole with your bur and then set the stop on your drill press so that the bur will drill no deeper. You want to drill until the girdle of the bur (the widest point on the bur) is just beneath the surface of the ring. The more metal that you want holding your stones in place, the deeper you want to drill. Please note that you must not drill deeper than the top cutting surface of the bur. If you do. it will be impossible to cut the channel.
- While maintain the spinning bur at this depth, click the index knob slowly. The bur will cut the channel as you click. Stop at the number of clicks you have predetermined is the correct length of channel. Stop the drill press.
- Loosen the expanding mandrel and remove the bur from the ring by sliding the ring so that the bur moves back out of the channel it has created.
You can now either create another channel on the same ring or put on another ring.