Power Supply, Fork Problems, Mating the Imaging Train

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Delivered the pier to Liberty at 8 AM.  Later in the afternoon, I called to find out if it was ready but was told that it would be Monday.  So that gave me time to pick up a Pyramid 12V regulated power supply from Durham radio at 4:15 PM.

Tonight, I had a go at placing the Parallax ring assembly in the forks. I mounted each of the two dovetail plates as supplied by Mathis using the eight supplied socket head stainless steel cap screws.  I then attached the two ring plates to each dovetail plate, and finally attached the two rings to the ring plates.  The fork separation, with the dovetail plates installed, is just over 538 mm, which is 5 mm more than the separation distance I specified to Mathis.  I e-mailed Mathis Instruments to describe the situation (seems that Mathis used the wrong spec.).  Mathis will fabricate a spacer.

I then attached the Van Slyke photo-visual imaging train and measured how much clearance I had left to clear the fork hub.  There is only 1-1/4" left - insufficient to clear with the QSI 516ws in place. I attempted to move the OTA so that the bottom ring wraps around the rear cell of the OTA.  However, the rear cell is just that much smaller in diameter to prevent the ring from getting a sufficient grip - the OTA slips in the rings, even with maximum compression applied to the top ring.

I placed two layers of green painters tape and a layer of anti-skid tape (normally used on starir steps) to the rear cell to slightly build up it's diameter and allow the bottom ring to provide sufficient grip. This prevented the OTA from slipping in the rings in this position. I re-attached the imaging train, and everything clears the fork hub, but the telescope is now nose heavy.  It looks like the ring plates will have to be shortened to 12" which will remove significant wait forward from the forks and will move the top ring back 6 inches.  This should provide better balance. In the meantime, I loosened the dovetail plates and slid the OTA back 35mm in the forks.  This provide the necessary balance to test drive the scope.