OnStep for GS-280 (old GSO) EQ telescope mount

thingiverse

Adapting the GS-280 (old GSO) EQ Telescope Mount to OnStep Goto Controller, by Howard Dutton Project. ### Accessories Recommended * OnStep Controller and Box on Base STM32 Blue Pill + [OnStep Controller and Box](https://www.thingiverse.com/thing:4057270) * OnStep SHC Smart Hand Controller + [OnStep SHC](https://www.thingiverse.com/thing:3212339) Alternative OnStep Mini 2.0 Controller and Box on Base MiniPCB2 and Teensy3.2 + [OnStep Mini 2.0 Controller and Box](https://www.thingiverse.com/thing:3404139) ### BOM * 2x JKM NEMA17 42BYGHW609 1.8 Degree Stepper Motor 40mm 1.7A * 2x GT2 Timing Belt 6mm wide 2mm pitch 170mm-2GT 85teeth * 2x GT2 Timing Pulley with 16 Teeth and Bore 5mm for 6mm belt * 2x GT2 Timing Pulley with 60 Teeth and Bore 8mm for 6mm belt * 16x M3x10mm Inbus screw * 2x M4x20mm Hex Head screws * 2x M4 wing nuts * 2x M4 Assortment * 18x 2x6mm self-tapping screws * 2x RA and DEC PCB + [RA and DEC PCB](https://easyeda.com/hujer.roman/ra_and_dec_pcb) * 2x RJ14 6P6C Right Angle PCB Jacks * 2x JST B4B-XH-A socket * 1x 3mm Red LED ### OnStep 4.x Config for TMC2130 Drivers (Vref=2.5V) <pre> //AXIS1 RA/AZM #define AXIS1_STEPS_PER_DEGREE 19200.00000 // 144t x 60/16 x 200 x 64/360 #define AXIS1_STEPS_PER_WORMROT 48000 #define AXIS1_DRIVER_MODEL TMC2130_QUIET #define AXIS1_DRIVER_MICROSTEPS 64 #define AXIS1_DRIVER_MICROSTEPS_GOTO OFF #define AXIS1_DRIVER_IHOLD 300 // (mA.) #define AXIS1_DRIVER_IRUN 1400 // (mA.) #define AXIS1_DRIVER_IGOTO 1680 // (mA.) #define AXIS1_DRIVER_REVERSE OFF #define AXIS1_DRIVER_STATUS TMC_SPI //AXIS2 DEC/ALT #define AXIS2_STEPS_PER_DEGREE 16000.00000 // 120t x 60/16 x 200 x 64/360 #define AXIS2_DRIVER_MODEL TMC2130_QUIET #define AXIS2_DRIVER_MICROSTEPS 64 #define AXIS2_DRIVER_MICROSTEPS_GOTO OFF #define AXIS2_DRIVER_IHOLD 300 // (mA.) #define AXIS2_DRIVER_IRUN 1400 // (mA.) #define AXIS2_DRIVER_IGOTO 1680 // (mA.) #define AXIS2_DRIVER_POWER_DOWN OFF #define AXIS2_DRIVER_REVERSE OFF #define AXIS2_DRIVER_STATUS TMC_SPI #define AXIS2_TANGENT_ARM OFF </pre> #### Note * Use the M3 thread mask for drill 2.5mm holes to cut the M3 thread in the original auger holders. * FreeCAD sources on [Github](https://github.com/romanhujer/OnStep-for-Seben-EQ3-mount/) #### Another Recommended Link: * [3D Printed - Small Travel EQ Telescope Mount](https://www.thingiverse.com/thing:3327081) * [OnStep for SEBEN EQ3 Mount](https://www.thingiverse.com/thing:2476084) * [OnStep for EQ5 (SkyWatcher) Mount](https://www.thingiverse.com/thing:4170058) * [My All Design for Astronomy Telescope](https://www.thingiverse.com/RomanHujer/collections/astronomy-telescope)