Procedure for Aligning Humphrey's Gyroscope
to the N=K=W Center Sub
The purpose of the alignment is to match the face of the gyro to the scope mounting slot of the center sub. This is needed because the thermal insulator attaches to the center sub with a threaded joint. The threaded connection allows for hardware exchange and versatility. The alignment only has to be done if the thermal insulator is unscrewed by mistake. For servicing the wire bundle running through the center sub, the insulator is removed by way of pushing on two locking pins holding the thermal insulator to the sub.
The basis of the alignment is to align two machined flats. One flat is on the center sub, and the other flat on the lower heat sink where the gyro is mounted. Once these flats are located on the same plane, the gyro is precisely aligned to the scope mount.
Looking at the picture below, the gyro attaches to the far left end of the heat sink by means of a 'J' slot. The 'J' slot aligns the gyro to the heat sink. The heat sink and the thermal insulator are one piece, and can not rotate from each other. The thermal insulator attaches to the center sub with a threaded joint that allows the operator to make the alignment orientation, and then lock it by way of a clamping thread. See the "Alignment Lock" shown in the photo.
Fig 1. Note the two Alignment Flats and the Alignment Lock.
Fig 2. For this picture, we have selected two common tools to be used as spacers: A punch and a chisel. For detail sake, the center sub and the heat sink are shown side-by-side. The large holes in the split nut and the center sub are used for rod wrenches (Steel rods 3/8" dia x 6" long).
Fig 3. This photo shows the center sub and the heat sink resting on their respective alignment flats. This alignment procedure does not need a level. Just a flat surface and 2 spacers. Notice that the 'J' slot is located on the top quadrant. The gyro's alignment pin fits inside this slot. Finally, tighten the locking threads at both extremities of the center sub as shown.