I want a magnetic stirrer for agitating developer/etchant while making circuit boards, but buying them on ebay costs ~$100-$200. I have a bunch of old hard drives lying around, so I'll be dismantling one and using the motor/magnets to make a stirrer!
Components
1×
Hard Drive motor
1×
Hard drive magnets
1×
Arduino/Microcontroller with PWM output and ADC input
1×
Potentiometer
1×
RC ESC
At least 2A... but I'm not even sure if 2A ESCs even exist. I'm using a 10A one.
So this project has been dead for a while, I just haven't been updating it.
Reason being, hard drive motors are completely unsuitable for this application. They are simply not designed to spin at low enough RPMs to perform this task, and therefore the project will not work at all.