Owner's manual

Irregular Pocket Milling Cycles
Chapter 25
25-2
Use the irregular pocket milling roughing cycle (G89.1) to rough out an
irregular pocket in a workpiece. This cycle makes multiple cuts at a
programmed depth, one cutter radius in width.
The G89.1 block used to rough out an irregular pocket has this format:
G89.1 X__Y__Z__P__Q__H__E__F__L__;
Where : Is :
XY
The coordinates thatspecify the start/endcornerofthe irregularpocketin the
selected plane. These parametersmustbeprogrammed.
Z
The coordinate (along the plungingaxis)thatspecifies the bottomofthe irregular
pocket. In incremental mode this parameterspecifies the depth ofthe pocketas
measured fromthe start-pointto the pocketbottom. This parameter mustbe
programmed.
P
The sequence numberofthe firstblock in the setofblocks thatdefine the pocket
shape. The coordinatesin thisblockspecify the end-pointofthepocket’sfirst
wall.
Q
The sequence numberofthe lastblock in the setofblocks thatdefine the pocket
shape. The coordinatesin thisblockspecify the end-pointofthepocket’slast
wall. Thisendpointmustcorrespondtothe start/endcornerspecifiedby the X
and Y coordinates. Thisparametermustbeprogrammed.
Important: T he setofblocks specifiedby Pand Q mustbe atleast5
blockslongtoqualify asan irregularpocket.
The setof blocks specified byP andQ may belocated anywhere inthesame
programas the G89.1 block. Theseblockscan notbecalledfrom a subprogram
ora macrounlesstheG89.1blockis in thatsubprogram ormacro.
H
The finishallowancethatwill be lefton the sidesofthe irregularpocket. This
finish allowance can be removedlater using aG89.2finishing cycle.
To leavea finishallowance on the pocketbottom,programapocketdepth(Z
parameter)thatisatthe desired finishallowanceabove the actual pocketbottom.
This finishallowance canbe removed laterusinga G89.1 roughingcycle
programmed with the actualpocketbottom.
E
Plungefeedrate. ThisparameterdeterminesthefeedrateofanyZ axismoves. If
notprogrammed the roughing feedrate (Fparameter) will be used.
F
Roughingfeedrate. This parameterdeterminesthefeedrateofany XYaxis
cuttingmoves. If notprogrammedtheexisting (modal)cutting feedratewillbe
used.
L
Incrementalplunge depth ofeachcuttingpass along the Z axis. Ifnot
programmed,theplunge amountwillbe equalto the programmed depth ofthe
pocket.
Before invoking the G89.1 cycle, t he programmer must activate cutter
compensation left or right by programming G41 or G42. This allows the
control to begin interpreting the blocks that define the contour of the
pocket as they a re encountered.
25.1.1
Irregular Pocket Roughing
(G89.1)