Small Travel 3D printed OnStep EQ mount for telescope

NOTICE NEW Harmonic drive version is now on HrEM

Sumary

It is new version 3D printed OnStep EQ telescope compact mount for OnStep goto controller , now use 17HS19-1684S-PG100 Nema 17 Stepper Motor with 99.05:1 Planetary Gearbox or 17HS15-1684S-HG100 Nema 17 Stepper Motor with 100:1 High Precision Planetary Gearbox (recommended for astrophotography)

Only RA axis can use for longtime astrophotography (Tracking speed is Sidereal, Lunar, or Solar)

- FreeCAD sources on Github

- RA and DEC PBC design is on EasyEDA

- My OnStep Mini 2.0 box on base MiniPCB2 and Teensy3.2 with drivers TMC2130

for 32 or 128microstep

or

- My OnStep Controller Box for on Arduino Mega2560 board with drivers DRV8825 for 32microstep

- Demo video

- Astrophotography gallery from this mount is here

BOM

16x M3x10mm screws

4x M5x60mm screws

1x M6x400mm threaded rod

10x 2.5x8mm self-tapping screws

20x 2x6mm self-tapping screws

6x M3 nuts

4x M6 nuts

4x M5 wing nuts

For HG100 High Precision Gearbox 8x M4x10mm imbus screw

8x M4 Assortmen

Optional for metal Clamp 2x QR-50 Quick Release Plate Clamp Mount Compatible For Arca SWISS

2x Metal clutch see Metal-clutch.pdf or Aluminum Shaft Coupler Bore Diameter: 5-8mm, DxL: 14x25mm and print key-clutch.stl

Optional for Polar scope holder 1x Skywatcher HM5 Polar Alignment Scope

1x Red Led 3mm

1x 50K Ohm 3296W Trimmer

1x Baterry 3V CR2016 (CR2025, CR2032)

3x M3x10mm screw

3x M3x25mm screw

2x 2.5x8mm self-tapping screws

(use a M3 tap to create a thread for screw)

I recommend using this right angle adapter for the polar viewfinder

Optional for Metal Weight

- DOMYOS CAST IRON WEIGHT TRAINING DISC WEIGHT 28MM 0.5 Kg

- M6 nuts

OnStep config.XXX.h

For 128microstep HG100 100:1 High Precision Planetary Gearbox

// Axis1 is for RA/Az // calculated as : stepper_steps* micro_steps* gear_reduction1* (gear_reduction2/360) // 17HS19-1684S-PG100: 200* 128* 1* 100 / 360 = #define StepsPerDegreeAxis1 7111.1111111