CALIBRATE YOUR MACHINE
Get your machine tweaked and running perfectly in no time!
GRBL CALIBRATION
I found a video that goes through it nicely: (Oct2016)
MACH3 CALIBRATION
LINK TO PRUSA CALCULATOR
GRBLCALC GRBL settings calculator for calculating steps/mm
FEEDS & SPEEDS
Additional Discussions:
The first discussion is here
Since updated and simplified in the C-Beam discussion
(with both of those links you may need to reload the page to get it to go to the correct post since the threads are long).
HOWTO Calibrate your CNC Machine for MACH3 or GRBL 2015-06-09
calibrate steps/unit