[jones89]

Hello.

So, instead of using the tools zero point to go home to tool change can I would like to use something that follows machine reference.
I've tried the G75 command but get the error code "approaching fixed point for transformed axix X1/X1 not possible" What am I'm doing wrong?

It's a lathe with revolver and y-axis Siemens 840d.

ex.

G54
WORKPIECE(,,,"CYLINDER",0,1,1339,1290,110)
;(TOOL - 1 OFFSET - 1)
;(C5-CP-25BL-35060-11B INSERT - NONE)
(FINECUT)
TRAFOOF
G40
G75 FP=1 X1=0 Z1=X
T1
TC(1)
G18
SETMS(4)
LIMS=3000
G96 S400 M4=3
G0 X105.828 Z-315.086 M108
G1 X103. Z-316.5 F.28
Z-613.152
G3 X103.8 Z-613.9 CR=.9
G1 Z-1270.
X110.
X112.828 Z-1268.586
M109
G0 X384. Z148.
M4=5
M30

¨

Thanks in advance. //

[CNCFr]

I guess you have got an inclined bed lathe.
With this type of machines the kinematic transformations (for example TRANSMIT) in reality is a concatenation of two transformation.
The first transformation converts the oblique machine coordinates into rectangular coordinates.
The second transformation converts the rectangular coordinates into the required format (for example into polar coordinates for TRANSMIT).
With TRAFOOF only the second transformation will be deactivated, the first transformation is "persistent". If this is true, you should see that the X1 axis is moving when you move the Y geometry axis (try with Jog in Y). So the X1 machine axis is still part of an active transformation and can not be moved with G75.
I'm sorry, but I don't remember if it is possible to deactivate the persistent transformation programmatically (i.e. without changing machine parameters).
And if it should be possible I don't remember how to do it.
But may be it helps to understand the problem.

[jones89]

CNCfr:

Thanks for reply. Yes its a inclined bed lathe. And your explanation makes sens. Thank you for your help!