Lathe indexing position

[Roger]

I just posted a question about mill, when I remembered one I had with lathe. Is there a way to set up lathe ver. 9 to index the turret a set distance from the part zero of the longest tool in the turret?

 

G0TOOO4

Z1.0

T0606

 

I have been editing the NC files to get this in my programs. It saves alot! of time.

[Steve Biehl - Cimquest Inc]

roger,

are you saying that 4 is your longest tool in this example and you would like the post to find the longest tool in the model and use that number?

[PE @ IHS]

CAM software has no way of knowing what your longest tool is unless you start using variables to set your offsets and include a macro in your post that reads these variables. In other words, it's too much work.

 

Tool offsets on a lathe are generally set in the machine, so the CNC program and the tool offsets are not at all related. In mills, you can set tools off-line, and input the length offsets via the G10 command.

[Roger]

I was saying that tool four was the longest tool.

 

Peter, maybe in version 10 they could incorporate this as a feature. Having a window that you could select your longest tool, and the distance to move away from your parts face. They could put it in the job setup, so that when your defining your part, chuck boundaries etc., you could also choose this as your "tool index position"

 

Thanks for the replies!

[PE @ IHS]

Hi Roger

 

I know what you meant by specifying the station of the longest tool. The problem is that the tool length that you specify in Mastercam does not necessarily reflect the exact length of the tool. The overhang is determined at the time that the collet/ bushing is tightened. By this point the program is already finished.

 

The geometry offsets on a lathe are determined at set-up time, not during programming, hence your original problem.

 

Peter Eigler

[Roger]

Peter, what you say is true. I have been programing a lathe for about a 1 1/2 years now. We have a bar puller so we can use up to 48" long stock. When I set up the lathe I will write down each tools position before programing, including which one sticks out the farthest from the turret face. (usually a drill, boring bar, or the bar puller.) This measurement is taken with a tape, in that it doesn't have to be that precise. I use the mpfan post, since the lathe has a fanuc controller. I then edit the NC file removing the move to home, and replacing it with

 

GO T0004 (longest tool)

Z1. (1 inch is enough clearance)

 

I also figure the number of parts I can get from the 48" and use a subprogam to call the main program that many times. So I can be running or programing the mills, while the lathe is running.

 

If there is a better way please! let me in on it. As I said before, by limiting the distance the tool turret moves before indexing saves hours! on cycle times. Thanks for your replies. I'm still new at this and I'm trying to become as efficient as I can at programing.