Last night I did some final tests and then connected my spool of magnet wire up and started a trial run of 10 turns. Everything went smooth, so I bumped the turns up to 890 and let ‘er rip. About 100 turns in, the carriage stopped moving 😦
After several more 100-turn tests, probing with the multimeter, and serial-debug from the Arduino, I determined that the DRV8825 was the culprit. I replaced it with a spare and was able to finish the last 200 turns without any trouble. Unfortunately, the winding wasn’t as pretty as I had hoped. That being said, it’s still better than the coils I made by hand on my old winding machine.
I also noticed that while I was moving the carriage exactly the diameter of the wire for every turn, sometimes the wire didn’t lie down that way, so I bumped the ratio down (from 60:1 to 55:1 coil-steps:carriage-steps) and that looked smoother.
The limit switches worked great, and you don’t have to be exact with them, which is nice. The wire seems to find its own way at the end of the spool.
Also, clamping the beginning of the wire between the spool and the neoprene washer was a great idea, it held that wire perfectly.
In the code, I used the name Coilatron 9000 for the machine, which is sticking so far.
Watch the video of my solenoid winding machine before it got all jacked up.