What about those Power Feeds?
There are two approaches. First of all, CNC’s have the ability to jog. Jogging is where
you’re spinning a simulated electronic handwheel, or holding down a button or joystick
to make the axis move. You generally select an axis, select a speed or multiplier (x1,
x5, x100 or whatever), and then operate the control to move the axis.Here is a typical pendant with an electronic handwheel (called an “MPG” or “Manual
Pulse Generator”) for jogging:
MDI quite simply stands for “Manual Data Input“, and that is what it is. You put your
machine into MDI mode, and it lets you directly type in G-Codes which are executed
immediately, instead of having to create and run a program. MDI is extremely useful to
know your way around. Check out this Mach3 Standard Mill home screen:
You can see the XYZ DRO’s (digital read outs) on the lower right. Just to the left of them is the MDI type in field. When not running a program, you can type G-Code commands into the MDI field for immediate execution. Look up in your operator’s manual how to go about
accessing MDI for your controller
