Rob Kean

doh! I forgot the current rating is per-phase. I'm also looking to experiment with one of the TMC2xxx drivers. I think the TMC2100 and TMC2208 should work as drop-in replacements, but the TMC2130 will require code changes to initialize the circuit. I won't know for certain until I experiment with them. Thanks for the response... I can't believe I overlooked that. -rob

After reviewing the omc-stepperonline website, I found another 27:1 stepper that appears to have the same stats, but a smaller gearbox. It appears the it reduces the weight from 500g to 400g. It costs about $5 more. I'm curious if the 1/4 lb. weight benefit would be worth it. Or if you are aware of any issues with using the smaller gearbox. 17HS13-0404S-CG27: https://www.omc-stepperonline.com/geared-stepper-motor/nema-17-stepper-bipolar-l33mm-w-gear-raio-51-small-planetary-gearbox-17hs13-0404s-cg27.html...