How to set Z offset for sub spindle

We have a Mazak SQT 18 MSY with mazatrol T-plus control, Our program machines the 1st end in main spindle, then it transfers part to sub spindle to machine 2nd end. During the transfer process it parts of the work piece. Everything is working Great, until We get to the end of the stock, and there is not enough stock to transfer the work piece and part off. So, we stopped program after it turns the 1st end, take out work piece and cut to length in saw. After our part run was over, we were going to put saw cut parts in sub spindle and finish second end. This is were our problem is, We wrote a simple little program for finishing just the second end. We can not figure out how to set the Z offset on sub spindle without doing a work piece transfer process. Any and All help would be GREATLY appreciated! I have read the manual and looked at the sample programs, can"t seem to figure it out. THANKS

You have to touch off on the end of your part in the second spindle with a tool for the second spindle and be sure this is an ACTIVE tool for the second spindle. Then move to the chuck a known amount and teach this position in your set up page. Now all your programming will be to this taught zero. You also will have to start your program with head one then go to head two right away. Or why don't you collect these and just finish them in the first chuck at the end of the run? You could make a split sleeve with a stop shoulder to go over the machined diameter to bring you back to your raw stock diameter.

Terry Z said:

You have to touch off on the end of your part in the second spindle with a tool for the second spindle and be sure this is an ACTIVE tool for the second spindle. Then move to the chuck a known amount and teach this position in your set up page. Now all your programming will be to this taught zero. You also will have to start your program with head one then go to head two right away. Or why don't you collect these and just finish them in the first chuck at the end of the run? You could make a split sleeve with a stop shoulder to go over the machined diameter to bring you back to your raw stock diameter.

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Your program offset is going to end up being a fairly large positive value, depending on the bed length.

Thanks Guys for the help, the next time I run this part I will try to set the Z on the sub spindle the way you have explained. The reason I just didn't use the main spindle, I didn't want to set up the (4) four tools I was using in the second operation again, plus I would have had to move some tools out to make room for the new tools, we use several of the same tools on many different parts of the same family. Once again Thank you for the ideas and advice. Sincerely, Jim