My son and I are hacking an old (1980s?) Dahlgren engraving machine that is driven by 3 steppers. The nameplate on the motors has voltage and current listed but nothing about steps, and Google doesn't turn anything up based on model, serial, manufacturer etc.
I tried to 'feel' the number of steps by rotating the shaft...can I assume that each detent (i.e. stop) represents one step?
We hooked up one of the steppers to a power supply and Arduino with an L298N-based motor shield, but can only seem to get it to twitch, vibrate and shudder no matter what we choose for the STEPS and SPEED arguments. We tried switching one set of leads in case we had the polarity backwards, but nothing different.
Is there a standard process for figuring out the number of steps?
I took a picture but can't figure out how to post it here (what do I put in between the tags?). They are pretty robust-looking motors and we didn't see an obvious way to get them open without harm to them or us.