Some basics................
The CNC Controller is a software Program called Mach 3 and provides for controlling all the movements and associated commands. The CNC controller (Mach) does not know a "practical" Machine Reference Point to work from, thus, the controllers “0,0,0” is somewhat meaningless and has unlimited movement capability. When the controller is turned on it monitors axis movement starting from Mach's “0,0,0” value for each axis and displays the absolute movement using Machine Coordinates.
Machine Zero is a fixed point within the physical machine travel limits and does not normally change. It is typically called Machine Reference point, machine zero, or simply Home Position. Machine zero can be located / defined anywhere by the user. Usualy it is located to provide for full available machine travel usage.
Part Coordinates are distances from a fixed point( machine zero as defined above ).
The controller needs to know where the part is relative to machine coordinates. The part zero can be located anywhere. The part has coordinates associated with it and normally the same location of the part is the basis for xyz= 0 in a gcode program. The software can’t properly control the machining of the part if it doesn’t know where the part is. Part coordinates can be equal to or even the same as Machine Coordinates. Thus defining the part location is very dependant on how a user sets up a job including how the gcode program was created. So part coordinates are used to relate or define where the part is relative to the machine coordinates.
In general, only the user can define where the part is located to the controller.
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A way to see how the controller keeps track of location /reacts to different button use is to go to the Diagnostics Screen and try different button's and watch the DRO's on the screen. Also change values in the DRO's and see the affect.
- Ref All Home
- Zero All, Ref axis button
- De Ref All Axes ( the button is on the MDI Screen )
- jog a defined step say 0.1"
KISS....only do a small move and one axis only
BTW,
The lathe has some different buttons.
Note that level of configured automation has an affect on intial state of the machine on
start-up.
FWIW,
RICH