Arduino, GRBL, Tb6600, and old motors

Robin2:
How have you adjusted the current (amps) limit on the TB6600 stepper driver?

I tried 2, 1.5, 1, and 0.5 .... at 0.5 the noise was a little better but I was completely unable to drive the motor.

What size is the motor?

I can try to measure it when I get home.

How many steps per revolution?

the data sheet says 1.8 degree per step so 200.