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All the individual shaft pieces were threaded, (16tpi), and after checking for overall length, etc. the threads were epoxyed and allowed to cure for several days. Each shaft was then turned on a lathe in a single setup to ensure linearity to within 0.0001"

Both the polar and declination shafts were fabricated from 2" aluminum tubing with 0.25" walls. Bearings with a 55mm ID were chosen as this would eliminate the need to turn the shafts down to accomodate the next smaller size bearing. Instead, the shafts were built up using short lengths of 2.25" aluminum rod. Additional lengths of 2.25" rod were used for the gear interfaces. Finally, 3" aluminum rod was used to fabricate the interface between the polar and declination shafts and the interface between the declinaton shaft and the dovetail saddle.