Control Stepper Motor with Core2 and GRBL 13.2

[tinymatt]

Hello,
I'm using the Core2 controller and the GRBL 13.2 module. I want to drive two stepper motors continually at a slow speed. The motors are attached to rollers, so they should be continuously rolling.

The motor I purchased is a Nema 17 bipolar from here: https://www.ebay.com.au/itm/175580114720

I have the motor turning using the example Arduino code, but the torque is very low; we can twist the axel easily.
What could be causing the toque to be so low? Have I specced the motor incorrectly, or do I need a different driver?
Thanks

[ajb2k3]

Could be alsorts like incorrect supply voltage, incorrect setting on the module or issues with the code.