Here is my program to do the NAS cone frustum. The program will run on any 840D machine because the block formats are kinematic independent. However, if run on a horizontal boring machine with a forked head (or a similar vertical machine), if the C-axis is not endless, it will have to be modified to rewind a C-axis that cannot do a full circle.
The program does circular interpolation of the path and conical interpolation of the orientation. It assumes a 2" side cutting end mill with approximately 6 inches of flute. The program does one pass. By changing b_radius to a smaller number and running again, it takes off more stock.
Email me at bleiercnctraining@gmail.com for more information.
;NAS 979 CONE FRUSTUM.MPF
N05 DEF REAL b_radius=5.6698
N10 DEF REAL _insert=1.40, _delta=0.4 ;the value ISD on the
figure next page
N15 DEF REAL _z_home=17 ;a retract position
N20 FGROUP(X,Y,Z);this is usually the default
N25 T2 ;2 inch cylindrical side cutter
N30 M6
N35 S1200 M3
N40 G0 SUPA Z=_z_home D0
N45 TRAORI
N50 ROT Y10 ;to get true 5-axis motion
N55 G54 G0 X=b_radius+1 Y=b_radius/3 A3=-sin(15) B3=0
C3=cos(15) M8
N60 Z0 D1 F=50 ;Z2.5 is top surface
N65 G64 CUT3DC ORIWKS
N70 East: G01 G41 X=b_radius Y=0 ISD=_insert A3=-sin(15)
B3=0 C3=cos(15)
N75 South: G02 X=0 Y=-b_radius CR=b_radius
ISD=_insert-_delta A3=0 B3=sin(15) C3=cos(15) ORICONCW A6=0 B6=0 C6=1
N80 West: G02 X=-b_radius Y=0 CR=b_radius
ISD=_insert-2*_delta A3=sin(15) B3=0 C3=cos(15) A6=0 B6=0 C6=1
N85 North: G02 X=0 Y=b_radius CR=b_radius ISD=_insert-_delta
A3=0 B3=-sin(15) C3=cos(15) A6=0 B6=0 C6=1
N90 East: G02 X=b_radius Y=0 CR=b_radius ISD=_insert
A3=-sin(15) B3=0 C3=cos(15) A6=0 B6=0 C6=1
N95 Escape: ORIVECT G1 X=b_radius Y=-b_radius/3 ISD=_insert
A3=-sin(15) B3=0 C3=cos(15)
N100 G40 G0 X10 A3=0 B3=0 C3=1
N105 ROT
N110 TRAFOOF
N115 G0 SUPA Z=_z_home D0 M3 M9
N120 M30
