[jsimon]

We are going to try and broach(shape) a keyway in a tapered bore on a CNC lathe with Fanuc 21i-TB controls and I need some help with the subprogram. The keyway is .3125 wide x .158 deep x 1.250 long with a 3.58° taper. The bore size is Ø2.2538 at the start and Ø2.4115 at the end. We are cutting cast iron. Here is what I have so far.

%
O4314 (KEYWAY)

( 4314 .3125 X .158 DEPP KEYWAY )

( 02/18/15 JES )

( KEYWAY CUTTER )

G99G20G0G54G40
G53X0.Z-18.0
M05
G54
G0T0101
G28H0.
G0X2.25382Z1.0C0.0
M68
M98P0002
G0G54Z1.0X#502
WHILE[#503LT#500]DO1
G0X#503M8
G1G98Z-1.3F250.0
G0X#502
G0Z1.0
#503=#503+#501
END1
G53X0Z-5.0
M01

O0002
(SUB FOR MACRO VARIBLE)
#500=2.5881(KEYWAY DEPTH)
#501=.001(DEPTH OF CUT)
#502=2.25(BORE SIZE)
#503=2.2538(START REFERENCE POINT)
M99


M30
%

Where do I put in the tapered information in the sub program?
Any help would be much appreciated.

[mcode]

Try this:

%
O4314 (KEYWAY)

( 4314 .3125 X .158 DEPP KEYWAY )

( 02/18/15 JES )

( KEYWAY CUTTER )

G99G20G0G54G40
G53X0.Z-18.0
M05
G54
G0T0101
G28H0.
G0X2.25382Z1.0C0.0
M68
M98P0002
G0G54Z1.0X#502
WHILE[#503LT#500]DO1
G0X#503M8
G1G98Z-1.3U-[#504]F250.0
(G0X#502 this would be a problem, could be U-.15 or something if needed)
G0Z1.0
#503=#503+#501
END1
G53X0Z-5.0
M01

O0002
(SUB FOR MACRO VARIBLE)
#500=2.5881(KEYWAY DEPTH)
#501=.001(DEPTH OF CUT)
#502=2.25(BORE SIZE)
#503=2.2538(START REFERENCE POINT)
#504=[[TAN[3.58]*2.3]*2](X DIA. DIST. FOR Z2.3 DIST. )
M99


M30
%

hope that helps

[Heavy_Metal]

Hi,

This (metric) program works on my Fanuc 18T.

You can try it with your own X Z values.
Cutting step in my program is 0.1, U6 minus U5.9 (3.5+2.4)

%
:0020( BROACHING )

T0202 G98 M86( M86 = C-AXIS ON )
G28 H0
G0 X30. Z50. C0
/M8
Z10.
M14( BRAKE ON )

M98 P650021

Z20.
M15( BRAKE RELEASE )
G00 Z150.
X275. M09
M85 (C-AXIS OFF)
M30

:0021( REPEAT 65X )
G01 G98 U6. F2500
G01 U-3.5 W-40. F5000
G01 U-2.4 F1000
G00 W40.
M99
%[/FONT]

[jsimon]

mcode - that worked great, thanks for your help.

[mcode]

Thanks for the update, I'm glad it worked out.