First steel diy CNC router build

[Neale]

Personally, I wouldn't bother. I doubt that your power supply is accurate to that level anyway, and it wouldn't make much difference if it were. It takes a bit of mind-adjustment but with these kinds of drivers and motors, the actual voltage as such isn't that important. The driver limits the motor current to whatever you have set, whatever the supply voltage, and the reason for wanting a higher voltage is that it allows the current to rise more quickly to the set value, taking into account motor inductance (which is why the experts on this forum bang on so much about low-inductance motors - it's just so that the current rise is quicker for a given supply voltage and it's the current that makes the motor go faster). Having a slightly lower voltage across the terminals means that the current rise will be very slightly slower but you ain't going to notice the difference in practice; for most of the stepper pulse the driver will be regulating the terminal voltage to less than this anyway.