I recently removed the internal stops on a VID-29 stepper. I’ve used this free-turning motor and an optical sensor to exerimentally test some operational limits of the motor. The test rig uses a photo-interruptor to determine the needle position:
A quick note about wiring harnesses for these motors. I’ve found it really handy to make harnesses from 4-wire CD audio cables. My harnesses use push-on connectors at the motor end so I never accidentally cook the motor by soldering to the motor pins.
Or more accurately, filing off the stops.
Recently Tim Hirzel asked if I knew of a source of motors without stops, or if the X25.168’s could be modified to remove the stops and open up the full 360 degrees of rotation.
Okay, time to figure out if the stops can be removed. Note that I’m working on a VID-29 clone, not a genuine Switec X25.168 here. There are 4 tiny screws that open the case revealing this:
For the second gauge in this build, I tried to get better placement of the current-limiting resistor. By placing it tight in the corner, it wont cast a shadow.
These photos show the LEDs at 100% brightness, but they are on PWM pins so I can control the intensity from the Arduino code.
Getting Started with the SwitecX25 Library
For Arduino IDE version 1.0 and later you can store user-contributed libraries in a subdirectory of your sketch directory named ‘libraries’. In fact you really should install them there to ensure that they persist when you upgrade the IDE.