System information

SECTION FOUR - PREPARATORY FUNCTIONS (G CODES)
Example 1: G28 (No axis movement)
Example 2: G91 G28 Z 0 (Z to -0.1 Relative to machine zero)
Example 3: X1 Y0 Z-2
G28 X3 X3 then X-10 (Relative to machine zero.)
Example 4: X-3 Y2 Z-8 Z
G28 Z-7 -7 then Z-0.1 (Relative to machine zero.)
G29 Z to -7
The G29 command is the converse of a G28. G29 will return the machine to the programmed
point via the last intermediate point stored by a G28 command. The command format is as
follows.
G29 X____ Y____ Z____
programmed point
In general, G28 is used for a tool change or part loading/unloading position. It is normally used
to move to the reference point only. For example, G91, G28, Z0, Z moves to reference point.
When G29 is executed by itself, only the axis that was commanded with the previous G28/G30
goes to the intermediate point.
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