I recently finished a Routy build (my first CNC), and am currently testing it. I have it connected to a Synthetos TinyG controller, powered by a 30V 20A power supply. I am having trouble with the travel on the X and Y axis, as it seems to be traveling a little short of the command that I give it. For instance, if I send the following command 'G0 Y20' (inch mode), it only travels about 19-1/2 inches. But, when I send G0 Y0, it returns exactly to the starting point. There seems to be no jitter in the movement, and if I execute the above two commands several times, it always returns to the original starting point. So, I'm thinking that the motors are not skipping steps. I have it configured as traveling 40mm per revolution of the motor, and was wanting to make sure this is correct. I'm using the 20 tooth GT2 pully and cooresponding GT2 belt, with 20 teeth and a 2mm tooth pitch, I'm coming up with 40mm per revolution. Am I missing something? Thanks, Jim N.