Fanuc OM tool offsets ignoring G54

[Dustydude]

Hi All,
I expect I am doing something stupid but I can't work this out.

If I enter tool offsets via touching tool 1 off a gauge block on the bed say - 250 and enter - 250 in tool height offset 1 and then have G54 say set at Z 100.

If I then mdi G54 G43 H01 Z0 my machine chords go to - 250 not -150 but my absolute go to - 150

It seems G54 is being ignored unless I have the whole concept wrong.

Help please
Dusty

I can't work out why this would be

 

[13engines]

The Machine Coordinate Display ignores any offset you have set anywhere. No matter what, it will always show the Machine Position referenced from the Zero Return or Home Position.

Take note of that idea. If you're ever wondering about something not acting correctly, you can always refer to the Machine Coordinate Display as a benchmark to work backwards from.

 

[Dustydude]

Hi,
But if I'm telling my tool to go to zero should it not account for the g54 offset? Ie In the situation explained shouldn't absolute be zero not - 150?

It was very late after a very frustrating evening in the workshop so I'm perhaps not explaining this well

I'm confused

Dusty

 

[sinha]

G54 say set at Z 100

This is probably not done correctly.

 

[angelw]

The Machine Coordinate Display ignores any offset you have set anywhere. No matter what, it will always show the Machine Position referenced from the Zero Return or Home Position.

In the case of the OP's exercise, the Machine Position Display should be Z-150.0, if Z100.0 is set in G54. The Machine Coordinate Position display will always display the distance the Axes have moved from the Zero Return Position. In the Op's case, that would be Z-150.0

If I enter tool offsets via touching tool 1 off a gauge block on the bed say - 250 and enter - 250 in tool height offset 1 and then have G54 say set at Z 100.

If I then mdi G54 G43 H01 Z0 my machine chords go to - 250 not -150 but my absolute go to - 150

Make sure you're looking at the Machine Position Display and not the Absolute Position Display. The Machine Position Display should read Z-150.0 for your example.

Take pictures of your Tool Length Offset Page and Work-shift Offset Page and Post them here for the Forum Members to view.

Regards,

Bill

 

[Dustydude]

Hi Bill,
Any ideas on whats going on or test I could do to ensure its not just me missing something?
Dusty

 

[angelw]

Any ideas on whats going on or test I could do to ensure its not just me missing something?

Hello Dusty,
Execute your G54 G43 H01 Z0 Block and then take a look at the Machine Position Display. You display all Position Displays (Incremental, Absolute and Machine) by pressing the "ALL" Soft Key when in Position Mode. When the Z Axis is at the Reference Return Position (Home Position), the Machine Position should display Z0.000. After the G54 G43 H01 executes, the Machine Position should display Z-150.0.

Regards,

Bill

 

[Dustydude]

Hi Bill,
I've done this many times now and regardless of the g54 z offset I use the machine z always indicates - 250.
It's like g54 is being ignored
I will send you a few screen shots thus evening.
I'm using a tool setter on the bed that zeros at - 250 (rounding for convenience)
Regardless of g54 offset z the tool just returns to the top of my setter if I do the command string you mention.

 

[sinha]

Change the sequence of operation.
First set G54, wherever you want. Then, set length offset. Use MEASUR softkey, if available.

 

[Dustydude]

Hi,
I have done this in the process of trying.
Nevertheless ideally I want to set tools and leave them set and just change my g54 to suit jobs. Pretty sure that's a must.

 

[Dustydude]

Hi Bill,
Just a heads up this is the same machine you helped me with that would not use the standard M6 T#
We resolved this but I still need to use M6 and T# on different lines of code and it doesn't work at all via MDI.
The machine was in storage and lost its sero parameters for machine zero. I managed to reset this but I am wondering if some other parameters could be wrong that's now causing this problem or any of the parameters we changed to get the tool change going?

Dusty

 

[sinha]

Hi,
I have done this in the process of trying.
Nevertheless ideally I want to set tools and leave them set and just change my g54 to suit jobs. Pretty sure that's a must.

Possibly you are not updating G54 correctly. Is MEASUR softkey available?

 

[Dustydude]

Hi,
Unfortunately no measure key on my OM
My setup is this

1. Zero home machine
2. Lower z until my tool 1 zeros my setter. In this case - 250
3. In tool offset table enter - 250 for height 1
4. Do the same for all other tools
5. Measure the z distance between the zero reference plane of my tool setter to the top of my job. In this case say the job is 100mm higher than my tool setter
6. In my g54 change z to 100

Its my logic but I'm no expert that all tool g43 h# z0 commands should now index to the top of my job if I gave such a command ie tool tips at zero

It doesn't do this they all go to their tool setting length I. E if I placed the tool setter under the tool and hit the command with g54 active they still index to the top of my tool setter not the top of the job.

That is my setup and even though I've been out the loop for years I'm sure this is how I used to do it.

Frustrating
Dusty

 

[sinha]

6. In my g54 change z to 100

What is displayed in G54 Z, before and after you change it to 100?

 

[Dustydude]

Hi
Zero before and 100 after.
Dusty

 

[angelw]

Hello Dusty,
On the Work-shift Offset page, you should have G54 onwards to G59, these will be labeled 1 to 6 also. There will be another Offset Registry on the first page labeled "0" and or, EXT. Set the G54 Z offset to Zero and enter +100.0 in the Z registry for the Offset Labeled "0".

With -250.0 set in the 01 Tool Offset registry, execute the following Block with the Control in Dry Run Mode and the Feed Rate Override Switch set to Zero. If Dry Run also controls Rapid Traverse (parameter dependent), the Distance To Go display should read Z-150.0 and the Z Machine Position Zero. Wind the Feed Rate up so that the motion occurs and the Z axis should end up at Z-150.0 from the Z Reference Return Position.

G90 G43 Z0.0 H01

If the Distance To Go when starting reads -250.0 in the Z display, you have an issue with the control, perhaps parameters. However, with regards to Option Parameters for the Work-shift Option, if the Work-shift Page displays correctly, normally you will have that option and it should work correctly without other parameter settings.

Regards,

Bill

 

[Dustydude]

Hello Dusty,
On the Work-shift Offset page, you should have G54 onwards to G59, these will be labeled 1 to 6 also. There will be another Offset Registry on the first page labeled "0" and or, EXT. Set the G54 Z offset to Zero and enter +100.0 in the Z registry for the Offset Labeled "0".

With -250.0 set in the 01 Tool Offset registry, execute the following Block with the Control in Dry Run Mode and the Feed Rate Override Switch set to Zero. If Dry Run also controls Rapid Traverse (parameter dependent), the Distance To Go display should read Z-150.0 and the Z Machine Position Zero. Wind the Feed Rate up so that the motion occurs and the Z axis should end up at Z-150.0 from the Z Reference Return Position.

G90 G43 Z0.0 H01

If the Distance To Go when starting reads -250.0 in the Z display, you have an issue with the control, perhaps parameters. However, with regards to Option Parameters for the Work-shift Option, if the Work-shift Page displays correctly, normally you will have that option and it should work correctly without other parameter settings.

Regards,

Bill

Hi Bill
No joy.
Distance to go - 250 and ends up machine - 250
Where do I go from here
Dusty

 

[dandrummerman21]

Can you post a screenshot of your code?

Are you doing this in MDI, and not memory? According to your screenshots the machine is in MDI mode.

 

[Dustydude]

Hi Dan,

Yes in mdi.

I will try in code. Could that make a difference?

 

[Dustydude]

Hi Dan,

Yes in mdi.

I will try in code. Could that make a difference