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Author Topic: Work offsets 101 ;)  (Read 2893 times)

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Offline Davek0974

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Work offsets 101 ;)
« on: April 11, 2016, 03:44:35 PM »
Is there a way to have Mach set G54 at the end of each job?

My reason -

I have a production part, uses a small fixture that is always mounted in the same place on my mini-mill so it seems setting G55 as my work offset makes sense.

AFIK Mach always uses G54 as the default work offset, which is fine, but once i run my parts (which call G55 at the start of the code) it will remain in G55 so forgetting call G54 again will create a mess??

So, is there a way to default back to G54 after each run so it reverts to a safe condition for other jobs??

Of course, if I'm going about this backwards then please let me know but this makes sense to me so far ;)

Offline Hood

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Re: Work offsets 101 ;)
« Reply #1 on: April 11, 2016, 04:26:09 PM »
Could you not just G54 at the end of your code?
Hood

Offline Davek0974

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Re: Work offsets 101 ;)
« Reply #2 on: April 11, 2016, 04:32:42 PM »
Yes that would work, ta.

There is no default in sheet-cam as that would be better - no chance of forgetting then but this will work.

Offline Hood

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Re: Work offsets 101 ;)
« Reply #3 on: April 11, 2016, 04:38:00 PM »
Can you not edit the post processor to add it?
I do similar on my Lathe, have the PP altered so that at the end of each run it will do a tool change back to slot 1 on my turret. Did this in Dolphin as well as BobCAD.

You can also add G54 to the Initialisation string on General Config and have the option for it to run on all Resets, not really a good option in my opinion as for starters you may forget and secondly, unless using a closed loop control such as CSMIO/IP-A, then each time you press Reset your axes will move slightly and Mach will not know, so you need to re-home.

Hood

Offline Davek0974

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Re: Work offsets 101 ;)
« Reply #4 on: April 11, 2016, 04:41:34 PM »
Hmm, i tried adding it to the process list in sheetcam, last item after all the cuts etc and this is the end code from a job...

N27150 (Operation: Insert code snippet Code: Apply Standard Offset G54)
N27160 G00 Z20.0000
N27170 G54
N27180 G00 X87.7841 Y384.6574 Z20.0000
N27190 X0.0000 Y0.0000
N27200 M05
N27210 M05 M30

Seems it is calling G54 as needed but it then issues move commands which would be in the wrong offset - this is wrong is it not??

Yes a post edit may be needed??

Offline Davek0974

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Re: Work offsets 101 ;)
« Reply #5 on: April 11, 2016, 04:45:33 PM »
Post edit seems better, now looks like this...

N27150 G00 Z20.0000
N27160 X0.0000 Y0.0000
N27170 M05
N27180 M05 M30
N27190 G54

Should it be before the M30??

Edit...

N27160 X0.0000 Y0.0000
N27170 M05
N27180 G54
N27190 M05 M30

Better ?   8) 8)
« Last Edit: April 11, 2016, 04:47:26 PM by Davek0974 »

Offline Hood

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Re: Work offsets 101 ;)
« Reply #6 on: April 11, 2016, 04:48:20 PM »
Yes should be before the M30 as the file will End and  rewind at the M30 .
Hood

Offline Davek0974

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Re: Work offsets 101 ;)
« Reply #7 on: April 11, 2016, 04:52:15 PM »
Sorted then, thanks :)

Offline Davek0974

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Re: Work offsets 101 ;)
« Reply #8 on: April 13, 2016, 01:41:14 PM »
Ok, I think i'll pass on work offsets at the moment.

I tried it tonight, with the G55 call in the start of the code, but it seems you need to be in G55 BEFORE you perform top-of-material sensing ??

I did not try a run because the numbers on the DRO's looked wrong to me and i didn't want waste a cutter and material.

I was also getting Soft-Limit on Z warnings when pressing cycle start so something was certainly wrong.

Clearly I do not understand offsets yet So i have resorted to writing down the X & Y offset for the job and just doing G0's to there and zeroing out the respective DRO.

After switching back to G54 and doing this it all worked as normal.


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