I'm learning to program Mazak lathes at my new job with no more than the manual and old programs to go by. These are bar-fed SQT lathes with subspindles and Fusion 640T controls.
Some of the programs I'm running will stop the bar extending from the chuck about 3 inches, do some machining, then advance the bar say another 3 inches to do some more machining.
The problem is, the Z-zero is still back at the first location. It seems like it'd be easy to shift the Z the same 3", so that the Z-zero is still at the end of the bar and the programming remains logical at a glance.
Any help would be appreciated, and pardon my hasty post if this is something I just overlooked in the book.
One solution is "program technique". In this case, it's employs the use of the Mazatrol END UNIT and linking programs. In the first feed program, the end unit is set to go to a different program for the second feed. The "switch" to run continuous should also be set.
The second program has it's own Z offset for the second feed out, which, because it's a new program, allows for a new Z offset value. Now, at the end of this program, the end unit sends you back to the other program, but the "continuous" switch is set to "no".
Or, if you want to run both continuous, put an M code unit in the first program with an M1 optional stop, and this will halt the program at the beginning of the first program.
The part doesn't care how many programs it took to make it. Each program has it's own Z-offset, so this is what you do for multiple feed parts.
This "program linkage" is also good for tiny boring bars, where the "global" stock allowance X & Z, which is tuned for O.D. turning, may break micro 100 tiny boring bars. Isolate the Bar In unit to a separate program and tune the stock allowance to suit the tiny delicate bar.
They fixed this in the Matrix Control, finally! Each unit allows the stock allowance X&Z to be specified anew.
-90% Jimmy, the mazak internet fairie