Smithy CNC Mills - Manual (Page 29)

* inverse time feed rate is active during a canned cycle,
* or cutter radius compensation is active during a canned cycle.
When the XY plane is active, the Z number is sticky,
and it is an error if:
* the Z number is missing and the same canned cycle was not already active,
* or the R number is less than the Z number.
When the XZ plane is active, the Y number is sticky, and it is an error if:
* the Y number is missing and the same canned cycle was not already active,
* or the R number is less than the Y number.
When the YZ plane is active, the X number is sticky, and it is an error if:
* the X number is missing and the same canned cycle was not already active,
* or the R number is less than the X number.
2.18.1 Preliminary and In-Between Motion
At the very beginning of the execution of any of the canned cycles, with the XY-
plane selected, if the current Z position is below the R position, the Z-axis
is traversed to the R position. This happens only once, regardless of the value of L.
In addition, at the beginning of the first cycle and each repeat, the following one or
two moves are made
1. a straight traverse parallel to the XY-plane to the given XY-position,
2. a straight traverse of the Z-axis only to the R position, if it is not already at the R
position.
If the XZ or YZ plane is active, the preliminary and in-between motions are analo-
gous.
2.18.2 G81: Drilling Cycle
The G81 cycle is intended for drilling. Program G81 X-
Y- Z- A- B- C- R- L-
SmithyCNC Programmer’s Reference Manual:G Codes
SmithyCNC Programmer’s Reference Manual: G-Codes 2-14