CANNED CYCLES REFERENCE

CANNED CYCLES REFERENCE

SUPPORTED CANNED CYCLES

  • G80: Cancel active canned cycle
  • G81: Simple drilling cycle
  • G82: Simple drilling with dwell cycle
  • G83: Peck drilling cycle
  • G73: High speed peck drilling cycle
  • G84: Tapping cycle
  • G85: Boring cycle – feedrate out
  • G86: Boring cycle – stop, rapid out
  • G88: Boring cycle – stop, manual out
  • G89: Boring cycle – dwell, feedrate out

All canned cycles are performed with respect to the active plane. The descriptions we use assume the XY-plane has been selected. The behavior is always analogous if the YZ- or XZ-plane is selected.

  • X~ is the X-axis coordinate
  • Y~ is the Y-axis coordinate
  • Z~ is the Z-axis coordinate
  • A~ is the A-axis coordinate
  • R~ is the retract position along the axis perpendicular to the currently selected plane (Z-axis for XY-plane, X-axis for YZ-plane, Y-axis for XZ-plane)
  • L~ is the L number is optional and represents the number of repeats

All canned cycles use X, Y, Z, and R words. The R word sets the retract position; this is along the axis perpendicular to the currently selected plane (Z-axis for XY-plane, X-axis for YZ-plane, Y-axis for XZ-plane). Some canned cycles use additional arguments.

Rotational axis (A-axis) words are allowed in canned cycles, but it’s better to omit them. If rotational axis words are used, the numbers must be the same as the current position numbers so that the rotational axes do not move.

The R number is always sticky — it keeps its value on subsequent blocks if they’re not explicitly programmed to be different.

In absolute distance mode (G90), the X, Y, R, and Z numbers are absolute positions in the current coordinate system.

In incremental distance mode (G91), when the XY-plane is selected, X, Y, and R numbers are treated as increments to the current position and Z as an increment from the Z-axis position before the move involving Z takes place; when the YZ- or XZ-plane is selected, treatment of the axis words is analogous.

Many canned cycles use the L word. The L word is optional and represents the number of repeats. L0 is not allowed. The L word is not sticky. The interpretation of the L word depends on the active distance mode:

  • In incremental distance mode (G91), L > 1 in incremental mode means (with the XY-plane selected), that the X and Y positions are determined by adding the given X and Y numbers either to the current X and Y positions (on the first iteration) or to the X and Y positions at the end of the previous go-around (on the subsequent repetitions). The R and Z positions do not change during the repeats
  • In absolute distance mode (G90), L > 1 means do the same cycle in the same place several times. Omitting the L word is equivalent to specifying L=1

The height of the retract move at the end of each repeat — called clear Z — is determined by the setting of the retract mode: either to the original Z position (if that is above the R position and the retract mode is G98) or otherwise to the R position.

TROUBLESHOOTING

It’s an error if:

  • X, Y, and Z words are all missing during a canned cycle
  • A P number is required and a negative P number is used
  • An L number is used that does not evaluate to a positive integer
  • Rotational axis motion is used during a canned cycle
  • Inverse time feed rate is active during a canned cycle
  • Cutter radius compensation is active during a canned cycle

When the XY plane is active, the Z number is sticky and it’s an error if:

  • The Z number is missing and the same canned cycle was not already active
  • The R number is less than the Z number

When the XZ plane is active, the Y number is sticky and it’s an error if:

  • The Y number is missing and the same canned cycle was not already active
  • The R number is less than the Y number

When the YZ plane is active, the X number is sticky and it’s an error if:

  • The X number is missing and the same canned cycle was not already active
  • The R number is less than the X number

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 will move in rapid motion 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:

  • A straight traverse parallel to the XY-plane to the given XY-position
  • 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 analogous.

CANNED CYCLES REFERENCE