Siemens 840D Tool length offset on Gantry Mill

[macauleymaddock]

Hi guys,

I've been scouring the internet and was hoping I could find some siemens experts on here.

I'm trying to program a new gantry mill with 840D control. The machine isn't reading the tool length offset from Spindle 2 when quoting D1.

Here's an extract of my program:

PROC TEST_PROGRAM
R1=-1000
N10 G71 G17 G0 G64 G90 G40
N15 SOFT FFWON
N20 M224;TOOL CHANGE BOTH HEADS
N30 M6T994
N40 M259;HEADS UNCOUPLED - DRIVE INDIPENDENTLY
N50 G53 G1 F10000 Y0.0 V0.0 Z500.0 W500.0 D0;POSITION HEADS FOR COUPLING
N55 Z400. W400. D1
N60 M256;COUPLE HEADS SYMETRICAL - SIDE 1 IS MASTER
N70 G54 G71 G17 G0 G64 G90 G40 G0
N80 X110.0 Y-175.
N90 G1 Z200.0 F2000 D1;CALL UP D1 TOOL LENGTH
N100 M0 ;CHECK SPINDLES ARE ALIGNED IN Z AND W
N105 M1=3 S1=700
N106 M2=4 S2=700
N110 G41 Y-130.15
N120 G1 X=R1 F10000
N130 G40 Y-175. F2000
N140 SUPA G0Z0.D0
N150 M259;HEADS UNCOUPLED - DRIVE INDIPENDENTLY
N160 M1=5 M2=5
N9999 M30

The machine will only read the tool length from Spindle 1 (XYZ axis).

If i wanted to write a subprogram to compensate for this i wanted to change line N50 in my program, but how would i access the tool length offset in spindle 2?

I saw some information in an old siemens manual which says you can read and write tool offsets from the NC program:
R100=$TC_DP994 [4,1] - This would write T994 length offset to parameter R100 which I could use.

I'm not sure how to access the tool length on spindle 2?

Any help would be greatly appreciated.

Macauley.

 

[manofwar17]

Hey Macualey, did you get this problem figured out? Seems like a master spindle issue. Are you running multi channel or single channel setup for the 2 different spindles? Also, the variable posted for tool length appears to be incorrect for the 840d control. You would need R100 = $TC_DP3[994,1].