Entering a new tool offset mid-part

Hi all

I'm getting to gross with a Haas mini mill, and am trying to wrap my head around tool offsets. I think I understand it reasonably now, but I have a question:

If I set all my tool z offsets, then run a part with G54 WCS, all is well. If I then run a different part, all I need to do is re-find my origin point to enter as G54. The mill then knows where all the tools are in relation to the new part. What happens if I break a tool, or decide I need a new tool? How do I set the tool offset for that new tool, since the part in the vise has different dimensions from when I originally set my tool offsets?

The only thing I can think of (which I thought of while writing this), is to ONLY set my tool offsets based on something that doesn't move with part changes - a point on the vise, or a block mounted elsewhere on the table. Would that be "correct"? Or is there a different way to do this?

Thanks in advance

Lee



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"If I set all my tool z offsets, then run a part with G54 WCS"? Are you setting tool lengths with the wcs G54 Z=0. as the top of your part ?
as long as the wcs G54 Z is moving with the part you should be able to use the part to touch off the tool length.
you may have to take the difference in wcs z into account and add it to the tool offset for the broken tool replacement

Ah, so the tool offset is always relative to the G54 (or whatever wcs is used) z value?

I guess my concern was that the tool offset value was an absolute value as the machine sees it. So if I touch off my tools on the top of my part (at G54 z0), then adding a new tool and touching off on the top of the new part (G54 Z0) would be incorrect.

But wouldn't that mean that the values listed in the tool offset table would change/update whenever G54 is changed?

Lee

Sent from my SM-N960U using Tapatalk

"But wouldn't that mean that the values listed in the tool offset table would change/update whenever G54 is changed?"

the tool offset numbers won't change. The update is that the control is using the next g54 Zx.xxx to know where to put the tool
to the control this is a math problem for it
when you say T1 go to Z0. the control will take the work co ordinate shift (G54 Z x.xxx ) , the tool offset and come up with a machine position to go to
once you change the WCS Zx.xxxx you would have to take this into account for setting new tools on top of the part