More trouble with this old Mori.... Relative/incremental??

Hi All,

I'm trying to write a program for this old mori seiki 2 axis lathe with a fanuc controller that I've inherited. My program goes to zero return, calls up tool 1, calls my G54 work offset, and then will only move incrementally.

When I have the right tool and I call the G54, my absolute values update correctly. It tells me my tool is 9" above in the x and 17" above in the Z. So I'm asking it to rapid move to X2. Z0. (2" above the part centerline, 0" from the part face. Well, instead of go there it tries to move 2" POSITIVE in the x axis FROM my zero return point making it alarm out. If i put the machine in zero return mode, get both green lights (telling me im correctly on the limit switches) and then go to MDI and type "G0 X2. Z0." it does exactly what I need it to. So I dont know why when its in the program in automatic mode it behaves differently.

Any thoughts??? thank you in advance!

Have you verified which way is X pos/neg on your machine?

Program it as a positive move and see if it works. I bet your X is still set up backwards.

Yes, a positive X movement sends the machine away from me toward the back of the machine and away from the chuck.

Seems like in the memory mode it is programming in incremental or g91. Find out the gcode for absolute positioning (might not be g90?) and then try it. The fact that it works in mdi seems like that defaults to absolute but for some reason the memory mode doesn’t.

Know what, I think i figured it out. In my code, i was calling up G55 (an empty offset) to zero-return at the beginning of the program. Then I was calling a G54 afterward. When I changed the first G54 to a G53 (machine coordinates) all of a sudden it works as intended now. Perhaps it only allows you to call one work offset per program?

On many older fanuc controls there is a switch - sometimes a toggle/physical switch, sometimes a software switch, called "Manual Absolute" or something similar. Make sure this switch is "on" or the machine will me in permanent incremental mode regardless of what the program code says.