Losmandy G11 OnStep Stepper Motor Mount for Telesciope

thingiverse

Revision 12 - May 8, 2020 - This is a custom mount designed for the OnStep project on a G11 Losmandy mount. The system utilizes a 60/20 tooth belt drive with a 5 mm shaft. To assemble and remove it easily, you will need bearings, a shaft, pulleys/belts, and a 5 mm to 6.35 mm adapter (links to all below). There are pass-through holes for both the NEMA 17 motor mount bolts and the two G11 mounting bolts. It's still debated whether this setup is better or worse than a direct drive system, but it provides an easy way to test each option. Note: I also machined down the groove on my G11 worm gear bearing block to get more space for the 0.25" worm gear shaft. 5 mm bearings (ID: 5mm, OD: 16 mm, thickness: 5 mm) https://www.amazon.com/XiKe-Precision-Bearings-Pre-Lubricated-Bearings/dp/B071RXC7FV/ref=sr_1_7?keywords=5mm+bearing&qid=1584036779&sr=8-7#feature-bullets-btf 5 mm shaft (any type will do, but here's one) https://www.amazon.com/Uxcell-a15113000ux1223-150mm-Model-Straight/dp/B01B5QTM8I/ref=sr_1_13?keywords=5mm+steel+shaft&qid=1584036840&sr=8-13 60/20 tooth drive and shaft (set of two, a good deal) https://www.amazon.com/Befenybay-Synchronous-Aluminum-Timing-20-60T-5B-6/dp/B07ZBZ739T/ref=sr_1_3?keywords=60+tooth+belt+5mm&qid=1584036919&sr=8-3 5 mm to 6.35 mm adapter - Many options are available for this. Note: These don't fit and need to be machined down, search for other options. https://www.amazon.com/uxcell-Aluminum-Coupling-Flexible-Connector/dp/B07G6PWJZ8/ref=sr_1_4?keywords=5mm+to+6.35+mm&qid=1584036962&sr=8-4 Here's another option - I haven't tried it, but it may be better as it has no windup. https://www.amazon.com/Huco-321-07-1416-Z-Coupling-Electroplated-Aluminum/dp/B004HW6Z7O/ref=sr_1_4?keywords=bellows+coupling+shaft&qid=1583958444&sr=8-4 Video of the 1:1 and 3:1 options using the 3D printed brackets: https://youtu.be/r9pGQRS9bSE Video of the reverse worm gear setup: https://youtu.be/yEvuvyM_T84