It is new version 3D printed - EQ telescope compact mount for [OnStep goto controller](https://groups.io/g/onstep/wiki/home), now use
...Show more [17HS19-1684S-PG100](https://www.omc-stepperonline.com/nema-17-stepper-motor-bipolar-l48mm-w-gear-raio-1001-planetary-gearbox-17hs19-1684s-pg100.html) Nema 17 Stepper Motor with 99.05:1 Planetary Gearbox.
Only RA axis can use for longtime astrophotography (Tracking speed is Sidereal, Lunar, or Solar)
* FreeCAD sources on [Github](https://github.com/romanhujer/Small-EQ-mount-OnStep/blob/master/eq-mount-V1.4.FCStd)
* RA and DEC PBC design is on [EasyEDA](https://easyeda.com/hujer.roman/3d-eq-mount)
* [My OnStep Mini 2.0 box](https://www.thingiverse.com/thing:3404139) on base [MiniPCB2](https://easyeda.com/hdutton/minipcb2) and Teensy3.2 with drivers TMC2130
for 32 or 128microstep
or
* [My OnStep Controller Box](https://www.thingiverse.com/thing:2748375) for on Arduino Mega2560 board with drivers DRV8825 for 32microstep
* [Demo video](https://youtu.be/tVlYURu9AsQ)
#####Screws and Nuts
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
#####OnStep config.XXX
For 128microstep
<pre>
// Axis1 is for RA/Az
// calculated as : stepper_steps * micro_steps * gear_reduction1 * (gear_reduction2/360)
// 17HS19-1684S-PG100: 200 * 128 * 1 * (99+104/2057) / 360 = 7043.59531
#define StepsPerDegreeAxis1 7043.59531
// Axis2 is for Dec/Alt
// calculated as : stepper_steps * micro_steps * gear_reduction1 * (gear_reduction2/360)
// 17HS19-1684S-PG100: 200 * 128 * 1 * (99+104/2057) / 360 = 7043.59531
#define StepsPerDegreeAxis2 7043.59531
// PEC, number of steps for a complete worm rotation (in RA)
// calculated as : (StepsPerDegreeAxis1*360)/gear_reduction2.
// 17HS19-1684S-PG100: (7043.59531*360)/(99+104/2057) = 6400
#define StepsPerWormRotationAxis1 25600L
</pre>
For 32microstep
<pre>
// Axis1 is for RA/Az
// calculated as : stepper_steps * micro_steps * gear_reduction1 * (gear_reduction2/360)
// 17HS19-1684S-PG100: 200 * 32 * 1 * (99+104/2057) / 360 = 1760.89883
#define StepsPerDegreeAxis1 1760.89883
// Axis2 is for Dec/Alt
// calculated as : stepper_steps * micro_steps * gear_reduction1 * (gear_reduction2/360)
// 17HS19-1684S-PG100: 200 * 32 * 1 * (99+104/2057) / 360 = 1760.89883
#define StepsPerDegreeAxis2 1760.89883
// PEC, number of steps for a complete worm rotation (in RA)
// calculated as : (StepsPerDegreeAxis1*360)/gear_reduction2.
// 17HS19-1684S-PG100: (1760.89883*360)/(99+104/2057) = 6400
#define StepsPerWormRotationAxis1 6400L
</pre>
#####Another recommended link:
* [OnStep SHC (Smart Hand Controller)](https://www.thingiverse.com/thing:3212339)
* [OnStep ST4 Handheld controller](https://www.thingiverse.com/thing:262611
