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

Postby maxpautsch » Sun Jan 14, 2018 12:15 pm

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
freecad_tab0.png
problem
freecad_tab0.png (135.57 KiB) Viewed 392 times
freecad_tab1.png
settings
freecad_tab1.png (36.96 KiB) Viewed 392 times
chrisb
Posts: 30780
Joined: Tue Mar 17, 2015 9:14 am

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

Postby chrisb » Sun Jan 14, 2018 1:07 pm

Can you upload your file please, preferably in a simplified version showing the issue.
You need at least FreeCAD 0.19.23300 to edit my current sketches.
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.
maxpautsch
Posts: 8
Joined: Sun Jan 14, 2018 11:40 am
Location: muc

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

Postby maxpautsch » 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.
Attachments
freecad_demo.fcstd
simplified version
(19.01 KiB) Downloaded 9 times
herbk
Posts: 1989
Joined: Mon Nov 03, 2014 3:45 pm
Location: Windsbach, Bavarya (Germany)

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

Postby herbk » Sun Jan 14, 2018 5:25 pm

I made a own model and have a simular problem.
tag_dressup.jpg
tag_dressup.jpg (57.25 KiB) Viewed 362 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 353 times
Gruß Herbert
maxpautsch
Posts: 8
Joined: Sun Jan 14, 2018 11:40 am
Location: muc

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

Postby maxpautsch » Sun Jan 14, 2018 6:26 pm

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
Posts: 30780
Joined: Tue Mar 17, 2015 9:14 am

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

Postby chrisb » Sun Jan 14, 2018 6:47 pm

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!
You need at least FreeCAD 0.19.23300 to edit my current sketches.
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.