Bugreport: 'Holding Tags' not working for circles

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maxpautsch
Posts: 8
Joined: Sun Jan 14, 2018 11:40 am
Location: muc

Bugreport: 'Holding Tags' not working for circles

Post by maxpautsch »

As https://freecadweb.org/wiki/Help_FreeCAD mentiones to first report possible bug in the forum:

When using the 'Tag Dressup' on a profile based on a circle, there is a problem with the lowes path segment. The path is not calculated correctly and would crash the end mill. This is not only in the preview but also in the generated g code.
While playing around to check what could be the problem, i could find a setting where the path seemed to be ok. However the correct output could not be reproduced!

Is this user trouble or can anybody confirm that this is a bug?

Nightly build installed on 13.01.18 (yesterday)

OS: Ubuntu 17.10
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.17.12920 (Git)
Build type: None
Branch: master
Hash: 8faa9f38bb70a598afc2bc39ea1645d416ab057e
Python version: 2.7.14
Qt version: 4.8.7
Coin version: 4.0.0a
OCC version: 7.1.0
Locale: German/Germany (de_DE)
Attachments
problem
problem
freecad_tab0.png (135.57 KiB) Viewed 703 times
settings
settings
freecad_tab1.png (36.96 KiB) Viewed 703 times
chrisb
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Joined: Tue Mar 17, 2015 9:14 am

Re: Bugreport: 'Holding Tags' not working for circles

Post by chrisb »

Can you upload your file please, preferably in a simplified version showing the issue.
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maxpautsch
Posts: 8
Joined: Sun Jan 14, 2018 11:40 am
Location: muc

Re: Bugreport: 'Holding Tags' not working for circles

Post by maxpautsch »

During the generation of the simplified version (see attachment) i found a new dependency:
the problem only occurs, if the 'Step Down' value is smaller than the height of the tag.

I changed the 'Step Down' value by hand. By default it is the tool diameter. I do not know if this is a good default. Perhaps this should be changed.
Attachments
freecad_demo.fcstd
simplified version
(19.01 KiB) Downloaded 16 times
herbk
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Location: Windsbach, Bavarya (Germany)

Re: Bugreport: 'Holding Tags' not working for circles

Post by herbk »

I made a own model and have a simular problem.
tag_dressup.jpg
tag_dressup.jpg (57.25 KiB) Viewed 673 times
Edit FC is 0.17 12920 to

Edit Edit: I have this wronk path only as long as the Tag Dressup GUI is open. If i finish the operation by clicking OK, the path gets OK.
tag_dressup_2.jpg
tag_dressup_2.jpg (46.54 KiB) Viewed 664 times
Gruß Herbert
maxpautsch
Posts: 8
Joined: Sun Jan 14, 2018 11:40 am
Location: muc

Re: Bugreport: 'Holding Tags' not working for circles

Post by maxpautsch »

The problem only seems to occur if a tool path matches exactly the top of the tag. It is not the last path layer but the one at the height of the tab which is not calculated correctly.

When looking at your screenshots, I guess you use a 3 mm tool and thus 3 mm height increments by default. You should be able to see the problem, if you set your tag height to 3 mm.

Thank you and have a nice evening!
chrisb
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Posts: 53933
Joined: Tue Mar 17, 2015 9:14 am

Re: Bugreport: 'Holding Tags' not working for circles

Post by chrisb »

maxpautsch wrote: Sun Jan 14, 2018 2:08 pm During the generation of the simplified version (see attachment) i found a new dependency:
the problem only occurs, if the 'Step Down' value is smaller than the height of the tag.

I changed the 'Step Down' value by hand. By default it is the tool diameter. I do not know if this is a good default. Perhaps this should be changed.
Hi Max, thanks for finding out. That's why I asked for a simplification, because it usually helps the developers to track the problem to its source.

I forgot in my last post: Welcome to the forum!
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.
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