Manual

Grooving/Cutoff Cycles
Chapter 23
23-4
The format for this cycle is:
G76X__Z__I__K__F__D__;
Where : Is :
X__ the locationwhere thelast groove iscut. If only onegroove isto becut do not
program X. This maybe programmedas either anincremental or absolutevalue.
Remember that itsvalue isalso affected bydiameter or radius modes(G07 and
G08).
Z__ the totaldepth of thegroove from theZ coordinate position of the tool priorto the
execution of the G76 block. If this cycle is to be used as a cut off cycle the depth
programmed here should drive thetool through theface of the part. This value
represents thelocation of thebottom of thegroove cut. This maybe
programmed as either an incremental or absolute value.
I__ the distancebetween eachgroove. If the distancebetween thelocation of the
last groove (programmed with X) and thenext to thelast groove isless thanthe
value programmed with I, then theI value isnot used todetermine theposition of
the last groove. The last grooveis always cut at thelocation programmed with
X. The I parameter isalways programmedas an incremental, radius value
regardless of thecurrent mode of thecontrol.
K__ the amount that thecutting toolinfeeds intothe workpiecewith eachstep. The
step is followed bya retract of amount e (set in AMP bythe systeminstaller).
The cutting tool theninfeeds intothe workpiecean amount K+ e, retractsan
amount e, infeeds K +e, retracts e, etc. This repeatsuntil thetotal
programmed depth of the groove Z is reached. When thisdepth isreached the
cutting tool stops infeedingand either shiftsan amount D (if programmed) or
retracts tothe startingcoordinate at rapidfeedrate. The K-wordis always
programmed as an incrementalvalue regardlessof the current mode of the
control.
F__ the desiredfeedrate for thegrooving infeedmoves. The valueentered withthis
parameter replacesthe currentlyactive feedrate. It is optionalin thegrooving
block. If F isnot programmed thecurrently activefeedrate isused.
D__ the sizeof the incrementalshift move madeby thetool whenthe fulldepth of a
cut off hasbeen reached. This parameter must beprogrammed evenif its value
is zerowhen not usingthis cycleas acutoff. A valueother than zerois assigned
to D only if thegrooving cycleis beingused asa cut off cycle. It is alwaysan
incremental valueregardless of thecurrent mode. The signof the value
programmed with the D parameter determines theshift direction andshould
move the tool awayfrom the part. Programming thisshift move helpsto provide
a good finish since thecutting tool isnot touching the part when it is retracted at
the rapid feedrate.
CAUTION: The shift programmed with a D parameter is
executed as a rapid move. Make sure that the cutting tool is
clear to shift at the end of the grooving cycle.