Replacement Stepper motor for CNC

Hey all,

Looking for a replacement stepper motor to replace a failed one on a cheap Chinese CNC I got several years ago.

The model on it is:
JLB Stepper motor

Looking online, it seems it’s a Nema 17, 1.8 Degree unit.

I’ve never specified or really worked with steppers before so am unsure of what specs are important and what can/can’t be changed.

Any chance someone can assist with a suitable replacement that’s in-stock please.
Physical size is not an issue.

I’ve done a metric ton of research but still not 100% sure on a few things, hence the request for help.

The board controlling it is a Woodpecker v2.8 GRBL board with RepRap Stepstick (StepStick - RepRap drivers using the A4988 chip.

The board is powered by a 24v/5.64A power supply, however there is a large 12v DC/DC converter section on the board that seem to be feeding the stepper motor drivers, and there is 12V across the caps on the A4988 drivers - So I’m guessing they are 12v?

Last thing I can think you’ll need is the length of the shaft would have to be a minimum 15mm. I can use longer but shorter might be an issue.

thanks in advance

Hi Jay,

You’ve covered most of the important specs (step angle, NEMA size), the only other things I would consider are:

  • Torque output - some motors are more efficient or would differently than others, so make sure your replacement has a similar torque output
  • Current limit - Just make sure it isn’t higher than your drivers can output so they don’t get too hot

Good luck with your CNC project! :slight_smile:

There is a useful table here:
NEMA 17 Stepper motor - RepRap

Shaft diameter is another parameter that should match, but 5mm seems to be standard. Unless you want to rewire the cable then the connector needs to be matched, but unfortunately that table doesn’t mention the connector type. But if you take a few measurements and find a few more details about your motor you should be able to match it to something in that table.

It is also useful to find out (or perhaps just guess) the manufacturers’ part numbering scheme. For instance, it is quite possible that ‘1352’ is code for current and volts, and ‘P4130’ is packaging or colour or something else that’s irrelevant.

1 Like