Hi,
I'm having trouble with my G-11 mount and I want to get some feedback on what I plan to do to fix it.
My Losmandy G-11/Gemini-1 mount is 12 years old; it's mostly in original condition except that I've replaced both worms with Ovision worms.? It's in a rolloff roof observatory and I use it every clear night for variable star studies, using some software I've written to automate imaging (so I'm usually not in the observatory when it is running).
A couple of weeks ago, the Oldham coupler on the RA worm disconnected, apparently slipped on the worm shaft.? I re-positioned it and it seemed to work fine. The next day the scope wasn't moving in RA again, so I checked and saw brass shavings near the Oldham coupler.? Apparently I hadn't tightened it enough and it was sliding on the worm shaft, so I made the set screws as tight as possible and that seemed to fix it.
Less than a week later, the scope stopped moving in RA again. This time I found that the gearbox on the RA motor had broken. The RA motor worked fine, but the shaft on the gearbox spun freely.
After a moment of panic when the Losmandy web site said the gearbox replacement was out of stock, I found that Anacortes stocked replacement parts for Losmandy, so I ordered it with 2 day delivery.? It arrived yesterday and I installed it, and of course tested it out.
Gemini is now reporting "RA motor lags", and when the mount slews in RA my SCT seems to visibly wobble like something is impeding smooth motion.? I realize now that since I usually operate my scope remotely, I may have been getting the motor lags error for some time without realizing it, and that this might explain my problems with the Oldham coupler and the failure of the gearbox.? It also occurs to me that I had to replace the RA motor about 6 years ago, so maybe I've had a problem with my RA mechanics for some time.
I'm not much of a hardware person, but I think I need to take the mount apart and clean off any 12-year-old gunk that must be causing a load on the drive.? In hindsight, the lack of maintenance on my mount would explain why I'm having hardware failures.
Any words of advice before I get started?
Thanks,
-Joe
