Sunday, September 24, 2023

Star Party

The Boise Astronomical Society did a star party for Payette Public Library last night so I hauled my 5" f/9 refractor out to share.  I was at first concerned that all I would have to show was the Moon, but Saturn appeared about 8:30.  There was still too much twilight and Moon glow to get a decent image but at 90x the rings were visible.  It is still nothing like using the 17.5" reflector but still satisfying for the general public.

Unfortunately, I neglected to aim the polar axis true north so tracking was horrible.  I misread the direction of the compass in Google Maps so I was aimed south.  That it tracked as well as it did is somewhat amazing.

I had some mechanical problems.  The diagonal that holds the eyepiece kept rotating clockwise. After some examination, I realized that the ring that holds the retaining screw had works its way loose.  Turning it counterclockwise and tightening solved the problem.

Some months back, I machined a ring bracket set to hold the finderscope.  The original cracked.  Unfortunately, what I made was from several individual pieces screwed together to simplify machining.  While I used two screws to hold the ring assembly to the base, it was not as tight as it should have been.  Even a little play means the very slippery acetal moves, which prevents a consistent alignment of finderscope and main scope.

I originally made this myself because the base slides into a weird dovetail base which I thought was proprietary to Photon Instruments. No, it is a Vixen finder standard so I ordered one for $35.  Made in Canada!

When I got home and reassembled the mount, the locking bolt that holds the counterweight to the shaft broke.  At least the plastic head broke.  This Losmandy GM8 is at least 30 years old so I cannot complain.  I ordered a new one from Losmandy that is solid steel.

This is embarrassing.  I want to thank Miguel for a good suggestion, but reply is no longer working; it says sign in to Google.  But I am.

1 comment:

  1. OT: I seem to recall a few posts of yours desiring thumbscrews in various applications. Make your own!

    This was a Duh! Moment for me.