I finally got around to cutting the MTA-UTA tubes to length; the only eyepiece that would come to focus with the focuser spacer in place is the Televue 55mm Plossl. If I pull the 3/4″ spacer, I can get a couple more eyepieces to come to focus, but in particular, the Nagler 31mm T5 apparently needs a ton of backfocus, and the camera wasn’t working either, so I needed to think about how much to chop off the tubes, and, because the mirror has extra-long collimation bolts, I figured that a full 2″ (3/4″ spacer, plus “a little more” to get the eyepieces to come to focus, plus a bunch of slop which can be taken up by the focuser or the collimation bolts) would probably work.

I really need a better metal-cutting setup. Chopping 2″ off the end of a piece of lumber is dead simple in my setup, but metal is problematic.

It took about half an hour to get the cutting jig set up, then I ran off the 6 poles in about 5 minutes.

Then I decided to replace the UTA tubes at the same time, which required another 45 minutes to set up the new jig (smaller tube, 1″ rather than 1-1/4″) and a couple of tries to get the cut right (my fence was set up wrong, so I was getting non-square cuts, which wasted a little tube material 🙁 ).

Once the tubes were cut and deburred, putting the scope back together was pretty quick, it took maybe 10 minutes.

Then I spent an hour or so, trying to get the telescope to balance. I am completely lost when it comes to figuring out how to remove twist from the rig, and Trixie has always had a bit. I can’t figure out if it’s the saddle, or the focuser, or what.

I tried adding a counterweight to the rear of the telescope (to offset the nose-heavy scope), I tried adding Pumpkin as a “guide” scope (although I will continue using Guido, and Pumpkin can’t see anything because the focuser is in the way… details) and sliding “counterweight”. This has actually been in the design from the very start, but I’ve never really been able to get Pumpkin to work piggybacked on Trixie, for a variety of reasons.

Anyway, the rig still has twist, and I’m at a loss to figure it out. I kept hoping that the moon would rise, but it’s coming up later (9 day moon) and is passing through the southern zodiac right now, so it was hiding behind the @#$%^ pine tree when I finally gave up in disgust.

Trixie needs to be collimated, and then I can go through the process of figuring out whether the tube modification was enough to bring the camera and Terminagler into focus.

Fun weekend project, I need an astro-buddy to bounce ideas off of.

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