Orion ED80T-CF Motorized Focuser

thingiverse

I created a motorized focuser for my Orion ED80T-CF refractor using an inexpensive stepper motor. By loosening two large knobs, the motor-gear assembly can be slid up to disengage the stepper motor and allow manual focusing to approximately the correct position. Then, the gear can be slid back down to engage the fine-focus knob's large gear, allowing the motor to do the final focusing. I'm controlling my motor using a Raspberry Pi 3B and PiFace Motor-Extra board. The control software is the Astroberry-Piface INDI driver project for use in Kstars/Ekos. However, the printed parts have no specific dependency on this. I printed mine in Raptor PLA on a Monoprice Mini. In addition to the printed parts, I used the following components: 8-32 set-screws, about 3/16" (x5) - to hold gears in place 8-32 button socket cap screw, 1/4" (x2) - to attach the cover plate 8-32 long set-screws, 1" (x2) - to clamp the slider to the main bracket with printed knobs 10-24 set screws, 1/4" (x2) - to hold the main bracket onto the focuser barrel A 3.5mm TRRS panel-mounted jack (x1) A 24BYJ48 5V stepper motor (I modified mine to convert from 5-wire uni-polar to 4-wire bi-polar by cutting the trace connecting the center points of the two motor windings to the red wire, which was only necessary because PiFace assumes a bi-polar motor) Contact me for assembly questions. Update: April 2019 - I uploaded a second version that cleans up the top look, corrects the stepper shaft hole in the slider plate and moves the jack hole to the front of the assembly so that the cable back to the control computer does not interfere with the draw tube. This version printed in Filastruder Pro PLA on CR10S Pro.