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17 Canned Cycles for Drilling
17.1.12 Boring Cycle/Back Boring Cycle (G87)
The cycle will be performed in two different ways.
Fig.
A. Boring Cycle, Manual Operation at Bottom Point
Unless the machine is provided with the facility of spindle orientation (parameter ORIENT1=0), the control will act according alternative "A".
The variables used in the cycle are
G17 G87 Xp__ Yp__ Zp__ R__ F__ L__ G18 G87 Zp__ Xp__ Yp__ R__ F__ L__ G19 G87 Yp__ Zp__ Xp__ R__ F__ L__
The spindle must be started in M3 when the cycle is started. The operations of the cycle are
1.
2.-
3.
4.-
5.boring as far as the bottom point with feed F
6.– spindle stop (M5)
–the control assumes STOP state (M0), from which the operator can get in one of the manual movement modes (JOG, INCREMENTAL JOG, or HANDLE) and operate the machine manually, for example retract the tool from the side of the hole then remove the tool from the hole. After returning AUTO mode machining can be continued by START.
7.with G99, START followed by
8.with G99, spindle
9.with G98, START followed by
10.with G98, spindle
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