Ghost tab when generating GCode for single object

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raemin
Newbie Member
Posts: 8
Joined: Sun Aug 29, 2021 8:07 am

Ghost tab when generating GCode for single object

Post by raemin » Tue Sep 07, 2021 3:42 pm

I just wanted to output the Gcode of a single object in my drawing, an additional 4th tab has appeared (?)

Here is the output (the expected tabs are highlighted in green, the unexpected one in orange)
Capture d’écran 2021-09-07 154451.jpg
Capture d’écran 2021-09-07 154451.jpg (65.05 KiB) Viewed 573 times
that's the drawing with the tabs as I intended to have them
Capture d’écran 2021-09-07 154613.jpg
Capture d’écran 2021-09-07 154613.jpg (58.92 KiB) Viewed 573 times
That's how I've selected the object to be converted to GCode
Capture d’écran 2021-09-07 154958.jpg
Capture d’écran 2021-09-07 154958.jpg (27.46 KiB) Viewed 573 times
Please note :
1) I have changed the processor from GrblMM to a custom one
2) there are other objects(and tabs) in the drawing (see DxF)
3) I've deleted all tabs including the camTab object and recreated all tabs, same story
...
4) last but not least, that's not such a huge issue, so no worries if there are no easy fix!
Attachments
CNC_z_axis.dxf
(3.19 MiB) Downloaded 6 times

raemin
Newbie Member
Posts: 8
Joined: Sun Aug 29, 2021 8:07 am

Re: Ghost tab when generating GCode for single object

Post by raemin » Fri Sep 10, 2021 1:54 pm

I think I managed to identify the issue somehow:

Whenever a group is created, this group has its own "home" (reference). The GCode paths are generated respective to the group home , not the drawing home.
.
I've made a file with three groups (one circle, one triangle, one rectangle),
GroupsDrawings.jpg
GroupsDrawings.jpg (112.62 KiB) Viewed 470 times
.
All these groups do have their "home" in their own center, here is the resulting Gcode:
GroupsResultingGCode.jpg
GroupsResultingGCode.jpg (59.1 KiB) Viewed 470 times
.
My "ghost tab" was from such a group.

It's a bit disturbing at first, only solution I've found so far is either to not use groups, or define the group reference on X=0 Y=0.
Attachments
TestGroupHome.nc
(4.82 KiB) Downloaded 4 times
TestGroupHome.dxf
(107.39 KiB) Downloaded 7 times

CVH
Premier Member
Posts: 1501
Joined: Wed Sep 27, 2017 4:17 pm

Re: Ghost tab when generating GCode for single object

Post by CVH » Fri Sep 10, 2021 2:26 pm

raemin wrote:
Fri Sep 10, 2021 1:54 pm
It's a bit disturbing at first, only solution I've found so far is either to not use groups, or define the group reference on X=0 Y=0.
Maybe it's a good idea to explode 'groups' aka Block References before one add CAM paths ...
  • Turn on Selection Filter (GF)
    Filter on 'Block Reference'
    Replace the current selection (first icon)
    Explode (XP)
    Recursively until no Block References remain.
Regards,
CVH

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