Update 2/3/25: Updated to version 1.5 which reduces the distance from the RA to DEC axis to a minimum. Also included two versions, one that mounts with a standard Vixen style dovetail and one that attached to the wedge directly.
Also changed to Precision Planetary Gearboxes – 17HS15-1584S-MG5 – https://www.omc-stepperonline.com/nema-17-stepper-motor-l-40mm-gear-ratio-5-1-mg-series-planetary-gearbox-17hs15-1584s-mg5
Recommended 3D Printer Filament – 3DXTECH CarbonX EZ PC+CF Filament 1.75mm 500g 3D Printing Filament
or – Polymaker Fiberon PPS-CF Filament, Black 1.75mm 500g Spool
Update 11-22-23: Changed to 5:1 gearbox stepper motors (see BoM on Google Drive Link.) This makes for MUCH faster go-to and slew rates as well as almost silent operation. I am much happier with this configuration.
Update 10/28/23: Added counterweight. Carbon fiber tubes filled with lead shot and epoxy. The mount can handle the weight of my telescope just fine, but my tripod can be a bit “tip-y.”
Notes:
- The Harmonic Drives might take a while to ship from China, so order those asap
- I used sendcutsend.com for the aluminum and carbon fiber plate parts
- You will need to make the round, aluminum “PLUG_BASE” part or source a machine shop to make that for you. It might be possible to 3D Print it, but I’m not sure that will be strong enough. All of the mount’s loading is carried by this part so be careful.
- The OnStep firmware and configuration that I’m using are included in the Google Drive Link. You will likely need to change some of those settings depending on your use.
Links:
Wedge for Equatorial Mode – https://s.click.aliexpress.com/e/_oEVrxKQ
or – https://s.click.aliexpress.com/e/_oDqfAEK
Rokinon 135mm f/2 lens – https://amzn.to/3QN8Uko
OnStep Open Source Telescope Control Software
