Smithy CNC Mills - Manual (Page 112)

SmithyCNC Programmer’s Reference Manual: Mill Canned Cycles 10-9
10.5 G83 Cycle
The G83 cycle is intended for deep drilling or milling with chip breaking. The
dwell in this cycle causes any long stringers (which are common when drilling in
aluminum) to be cut off. This cycle takes a Q value which represents a "delta"
increment along the Z-axis. Machinists often refer to this as peck drilling.
0. Preliminary motion, as described above.
1. Move the Z-axis only at the current feed rate downward by delta or to the Z
position, whichever is less deep.
2. Dwell for 0.25 second.
3. Retract at traverse rate to clear Z
4. Repeat steps 1 - 3 until the Z position is reached.
5. Retract the Z-axis at traverse rate to clear Z.
NIST lists the elements of the command as G83 X- Y- Z- A- B- C- R- L- Q-
I find this command very handy for many of my deep drilling projects. I have
not tried to use the L for a repeat so can't say much about that feature. A typi-
cal g83 line that I would write might look like G83 X0.285 Y0.00 Z-0.500 R0.2
L1 Q0.05. EMC moves to position X0.285 Y0.00 at the z height before the block.
It then pecks its way down to Z-0.500. Each peck pulls the drill tip up to R0.2
after moving Q0.05.
10.6 G84 Cycle
The G84 cycle is intended for right-hand tapping.
0. Preliminary motion, as described above.
1. Start speed-feed synchronization.
2. Move the Z-axis only at the current feed rate to the Z position.
3. Stop the spindle.
4. Start the spindle counterclockwise.
5. Retract the Z-axis at the current feed rate to clear Z.