"A" Dop reference point or radial alignment: This is a cone pointed set screw in the dop arm 1 ¼ " from the end of the collet chuck. The purpose of this reference point is to radio align the grooved dops into a fixed position., i.e.: the groove of the dop corresponds with the cone point when the dop is inserted into the collet chuck. The reference point (cone pointed set screw) is properly adjusted when the grooved dop will slide easily into radial alignment. If the set screw is adjusted in too far then it will bind in the groove of the dop. DO NOT adjust the set screw against the groove of the dop after inserting the dop into the chuck. Before tightening the collet chuck turn the dop against the set screw. This will remove any error between the groove of the dop and the set screw. The gem is now cut after which the transfer set screws in the transfer block keeps the dops in proper alignment while the transfer is accomplished. After transferring is completed, the new dop is inserted into the collet chuck so that the groove of the dop and the cone point will correspond as previously mentioned. However, the direction that the dop must be turned to remove error of the sliding fit must be reversed to that established before the transfer. This reversal in the rotation of the dop is due to the fact that the relation of the gem to the reference point has been reversed throughout the transfer sequence. I.e.: if the second dop or transfer dop must be turned against the reference point counter clockwise. The reference point of the dop arm also allows the operator to remove and then re-insert the dop and gem during any phase of the cutting or polishing operation. The cone pointed set screws in the transfer block are also adjustable with the long 5/64" allen set screw wrench. These set screws will be properly adjusted when the dop will slide within the "V" way without any rotation. Important: Do Not adjust these set screws too high as this will tend to interfere with the parallel alignment of the dops. "B" Radio tooth index splitter: Knob is marked "R", "L", right and left turn calibrated with 5 degree increments. "C" Free wheeling pin: This pin when inserted will allow the dop arm to be turned without the trigger engaging the index gear. This allows the operator to round or preform the gem. The pin is removed to engage the index trigger with the index gear. "D" The index gear may be removed by loosening the allen set screw in the gear hub (use the 5/64" allen wrench). Note the flat on the dop arm shaft. The allen set screw of the index gear must be tightened on this spot only. "E" Compound Pivot Bolt: This bolt is loosened when an adjustment of the compound angle splitter is needed. After adjustment is accomplished re-tighten this bolt. "F" Quadometer Lock-out Screw "G" The two jib screws and locking nuts are used for adjustment of the mast or upright bearings. "H" The brass thumb screw "H" allows the operator to adjust the amount of torque needed to raise or lower the dop arm. I.e.: a brake. When adjusted properly, the brake will prevent the dop arm from falling onto the lap. "I" Positive angle stop: To adjust; loosen knurled knob, move dop arm until desired angle reading is noted on angle dial. Next, rotate angle stop counter-clockwise on pivot shaft until stop is in contact with yolk, then tighten. "J" Micro Angle Stop Fine Adjustment: Fine adjustment of the angle stop is accomplished by turning the knurled knob clockwise—plus (+) reading on the protractor. Counter-Clockwise—minus (-) reading on the protractor. "K" Quad-O-Meter Pressure Gauge: For repeat pressure reading. Registers the pressure that the operator exerts on the dop arm. The face of the dial can be adjusted or turned so that a light or heavy pressure can be registered. For a light pressure the indicator at rest should read .001 to .002 minus the zero. For a heavy pressure .003 to .006 minus zero. Pressure is then exerted by the operator on the dop arm until the indicator pointer reaches zero. "L" 6" Protractor + ¼ " Vernier Scale "M" Micro Height Knob: Turn clockwise for down and counter-clockwise for up. PRISMATIC INSTRUMENTS INC.
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