OTA Ring Mods, Fork Spacing, Testing Mount Park Modes

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The pier wasn't ready today, but I went to Durmach machine shop to discuss shortening the OTA ring plates from 18" to 12" and replicating the mounting holes in one end. The staff at Durmach in general and Dave in particular are real nice.  Should be about $50.  I hope to get it to them Wednesday.

At 4:30 PM, I had to disassemble the OTA and rings from the mount so that I could confirm the trunnion diameters, bolt hole pattern, and required new screw lengths to accommodate the 5mm fork spacer.  This also gave me the chance to get the forks oriented with the DEC gear fork on the west. Got everything apart, took the measurements to e-mail to Mathis. The trunnion (without the DEC gear) is 112 mm (~4.4") in diameter. The trunnion with the DEC gear is 112.5 mm in diameter. The dovetail plates bolt to the trunnions on a 4 inch bolt circle using 0.5" screws.  The screws thread into the trunnions 6mm (0.25").  With the 5 or 6mm spacer, we'll need 0.75" screws. Put the rings and OTA back in the mount with the DEC gear to the west.

Also got the "gunk" out of one of the small socket head screws that secure the trapezoidal motor cover, and was able to get the screw threaded in without he allen wrench slipping in the socket head. Pointed the scope near the zenith and meridian and simulated a sync on Menkalinan (Beta Aur), then tried out some slews to various objects known to be above the horizon.  When attempting a slew to an object below the horizon, the mount indicates such and aborts without moving. Tested out the various park modes, and mode 1 is the preferred - points telescope to the meridian and on south horizon (zero degrees altitude).  Sometime later (after a number of slews) the park 1 position has the mount pointing to the north horizon, and on the meridian.  More testing required.