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.
Disassembling a stepper motor is a bad idea as it apparently causes permanent damage to the motor.
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It has 4 wires and we measured the resistance to get the pairs right. It is still possible to get one set of coils 'backwards' relative to the other, correct? We switched one set to check and it didn't make a difference.
Thanks that is very helpful. The second page of the spec sheet seems to indicate that there is a 4-wire configuration, which would match what we have. I believe we tried as high as 200 steps but now that I know it is in that range we at least have a good starting point.
200 steps / 1.8 degree is standard and most likely what you have. I have seen steppers with 0.9 degree and 7.2 degree steps, but those are the smaller "pancake" type of steppers.
