4.35f Gxx Z offset issue

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4.35f Gxx Z offset issue

Post by cwatson1982 » Thu Feb 04, 2021 10:16 pm

I had a weird issue today. I recently upgraded to 4.35f, this was my first time running it. Every time I would set Z zero for G54 with a previously measured tool, then switch to another tool my Z zero would be off by a considerable amount (> .2).

I went through the entire process multiple times to make sure it wasn't me:

Set t19 length using my dial indicator tool setter
Set t23 length
Use t23 to set Z zero on my part
Switch to t19, Z zero is now off significantly
Switch back and check with t23, Z zero is off the same amount.
verified without physically changing the tool out or moving the Z axis at all that the same thing happened. (set t19 length, set Z zero using t19, switch to another tool via the menu while leaving t19 in the spindle and the Z axis in the same spot, switch back to t19 via the menu, Z zero is now off)

The tool lengths were correct after re-measuring them.

Eventually I rebooted the PC and cycled power to kflop/kanalog. The problem vanished.

Any idea where to look for potential issues? This kind of a scary one to have randomly pop up; I am running the program now and verifying zero is still correct after every tool change. :)

I'll respond when it is finished and attach my toolchange program and tool height set program

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Re: 4.35f Gxx Z offset issue

Post by TomKerekes » Fri Feb 05, 2021 12:27 am

Strange. I can't think of what might cause such behavior. I think the way I would approach it is to break it down to see what changed before/after the shift. There is the machine coordinate and 3 offsets: (G52/G92), Fixture, and Tool. They should have this relationship (with Tool length Compensation on):

Machine = DRO + G52 + Fixture + Tool


DRO = Machine - G52 - Fixture - Tool

Tom Kerekes
Dynomotion, Inc.

Posts: 31
Joined: Tue Jun 02, 2020 11:14 pm

Re: 4.35f Gxx Z offset issue

Post by cwatson1982 » Fri Feb 05, 2021 1:49 am

ToolChange1.c (m6)
ToolTableSetRev1.c (user button to set tool height as distance from home)

Tools are jogged down to a dial gauge type tool setter with a 4" gauge height.
Z zero is set with the same setter and then 4" is subtracted.
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