1. G Function Description
Notes:
1. before G74, use M Code let drill start to rotate CCW
2. if M Code and G74 are specified in the same block ,this M Code
only executes in the first time of positioning in that block
3. when K is used to specify numbers of times, this M Code is
executed for the first only, for the second hole and subsequent
holes, the M Code is not executed. G74 is module G Code ,it is
always effective when we use once ,we only specify (X,Y) in next
line of program ,controller will execute drilling at (X,Y)
4. this module G code ,use G80 to cancel ,when program run into
G00 , G01, G02 , G03 or other cycle ,this module G code will be
canceled automatically,
5. because there is a little time when spindle CW to CCW in
tapping ,please use P add dwell in G code
Condition:
1. before drilling axis be changed, Canned Cycle must be canceled
first.
2. if the Block does not include movement command of any axes (X,
Y, Z), then drilling will not be executed.
3. data that R specified only be set in blocks of executing drilling, it
can not be set in blocks of no executing drilling.
4. G code 01 group and G74 can be specified in the same block, or
G74 Canned Cycle will be canceled.
5. in Canned Cycle, tool length compensation(G41/G42/G40) will be
ignored.
Program example:
F1000. S500;
G90;
G00 X0. Y0. Z10.; // positioning to initial point
G17;
M04; // start drill to rotate CCW
G90 G99;
//specify point R、point Z and hole 1 coordinate values, dwell 2 s
G74 X5. Y5. Z-10. R-5. P2.;
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