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This is Bill's design for an extremely rigid tripod. All the square tubing has a wall thickness of 1/16". The total weight of the tripod is 40 pounds - very light. With this tripod design I was able to develop a method to align the telescope on the true north pole. First the telescope was optically aligned on Polaris. By knowing the right ascension and declination of polaris at the moment in time I was observing Polaris I was able to determine the azimuth and altitude distance Polaris was from the true north pole with formulas that translate right ascension and declination to azimuth and altitude. Then, the telescope was pointed to the true north pole by making the appropriate number of turns (clockwise or counterclockwise) of the 1" treaded rod of the south leg. The south leg is the one closest to Bill in the background. The east leg was the pivot point for azimuth. The azimuth adjustment was made by making the appropriate number of turns to move the plate under the west leg.

 

A close-up of the sliding plate for adjusting azimuth.

1977 was before the time of lap tops. I made this 'setting circle' for alignment on the true north pole. By pointing to the time of the year, I could read off the number of clockwise or counterclockwise turns to make in azimuth and altitude.

 
 

The plastic cover was taken off to show the right ascension drive. If you haven't noticed, there are letters in the image. "A" is the spring loaded adjustment to control for backlash in the primary worm and worm gear. The Primary  worm gear has about 510 teeth. "B" is the canister holding the small DC tape recorder motor. "C" is the small wheel, just barely showing, with a neoprene O-ring that turns the gears. The conical shaped part it turns was made conical shaped to be able to adjust the right ascension speed. "D" is the first worm gear. It has 110 teeth. "E" is the second worm gear which can barely be seen. It has 108 teeth. "F" is the knob for manually turning right ascension.

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