NCT Group 99M, 2000M manual Examples of modal drilling codes and cycle variables

17 Canned Cycles for Drilling

Cut-in value (Q)

It is the depth of the cut-in, in the cycles of G73 and G83. It is invariably an incremental, rectangular positive data (a modal one). Its value will be deleted by G80 or by the codes of the interpolation group. The scaling does not affect the value of cut-in depth.

Auxiliary data (E)

The extent of retraction in the cycle of G73 and value of clearance in the cycle of G83 is specified on address E. It is always an incremental, rectangular, positive data. The scaling command has no effect to the auxiliary data. (Modal value). Its value will be deleted by G80 or by the codes of the interpolation group. Unless it has been programmed, the control will take the necessary value from parameter RETG73, or CLEG83.

Dwell (P)

Specifies the time of dwell at the bottom of the hole. Its specification is governed by the rules described at G04. The value of the dwell is a modal one deleted by G80 or by the codes of the interpolation group.

Feed (F)

It will define the feed. A modal value, re-written only by the programming of another data F. It will not be deleted by G80 or some other code.

Spindle speed (S)

A modal value re-written only by programming another data S. It will not be deleted by G80 or some other code.

Number of repetitions (L)

Defining the number of cycle repetitions over the range of 1 through 9999. Unless L is filled in, the value of L=1 is assumed. In the case of L=0 the data of the cycle will be stored but not executed. The value of L is effective only in the block in which it has been specified.

Examples of modal drilling codes and cycle variables:

N1 G17 G0 Z_ M3

N2 G81 X_ Y_ Z_ R_ F_

It is mandatory to specify the data of drilling (Z, R) at the beginning of cycle mode.

N3 X_

Since the data of drilling have been specified in block N2 and they are used unchanged in N3, they need not be filled in again, i.e., G81, Z_, R_, F_ may be omitted. The position of the hole is varied in direction X only, the tool moves in that direction and will drill the same hole as in block N2.

N4 G82 Y_ Z_ P_

The position of the hole is shifted in direction Y. The method of drilling complies with G82, the bottom point assumes a new value (Z), the point R and the feed (R, F) are taken from block N2.

N5 G80 M5

The cycle mode and the modal cycle variables (except for F) will be deleted.

N6 G85 Y_ Z_ R_ P_ M3

Since the data of drilling are deleted in block N5 under the command of G80, the values of Z, R and P have to be specified again.

N7 G0 X_ Y_

The cycle mode and the modal cycle variables (except for F) will be deleted.

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