Grooving around datumline

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jze
Posts: 17
Joined: Thu Sep 30, 2021 9:11 pm

Grooving around datumline

Post by jze »

Hello,

I am trying to groove a groove in the arc (see attached picture). I selected the arc face, created 2 datum points in the center of the arc and created datum line from them. Now when I try to groove around this datumline (support axis) the groove is weirdly deformed (see attached picture).
Is it a bug or am I doing it wrong?
Attachments
V-vzpěra2.FCStd
(136.52 KiB) Downloaded 25 times
After groove
After groove
Snímek obrazovky_2021-10-24_12-34-30.png (165.93 KiB) Viewed 963 times
Before groove
Before groove
Snímek obrazovky_2021-10-24_12-32-41.png (154.22 KiB) Viewed 963 times
drmacro
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Posts: 8870
Joined: Sun Mar 02, 2014 4:35 pm

Re: Grooving around datumline

Post by drmacro »

Sketch001, Sketch002, and Sketch003 are all attached to generated geometry.

This has created a Topological Naming Problem (TNP) condition.

I think Pocket, Pocket001, and Pocket002 should be Pad, not Pocket operations.

Once these are corrected I think it will work correctly.

See here for further details:

Topological naming problem
Advice for creating stable models
Basic Attachment Tutorial
Star Trek II: The Wrath of Khan: Spock: "...His pattern indicates two-dimensional thinking."
jze
Posts: 17
Joined: Thu Sep 30, 2021 9:11 pm

Re: Grooving around datumline

Post by jze »

I have no idea how to make a pocket using a pad....
jze
Posts: 17
Joined: Thu Sep 30, 2021 9:11 pm

Re: Grooving around datumline

Post by jze »

And the https://wiki.freecadweb.org/Topological_naming_problem describes a bug. And at the 7.) it describes a puzzle in Klingon language.
drmacro
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Posts: 8870
Joined: Sun Mar 02, 2014 4:35 pm

Re: Grooving around datumline

Post by drmacro »

jze wrote: Sun Oct 24, 2021 12:06 pm And the https://wiki.freecadweb.org/Topological_naming_problem describes a bug. And at the 7.) it describes a puzzle in Klingon language.
Sorry, I misinterpreted one of the pockets.

None the less, I see no Klingon problem in the link.

Here is your file with the TNP mitigation addressed and an example of less complicated approach.
Snip macro screenshot-f68e19.png
Snip macro screenshot-f68e19.png (85.28 KiB) Viewed 852 times
Attachments
V-vzpěra2-mac.FCStd
(58.9 KiB) Downloaded 15 times
Star Trek II: The Wrath of Khan: Spock: "...His pattern indicates two-dimensional thinking."
jze
Posts: 17
Joined: Thu Sep 30, 2021 9:11 pm

Re: Grooving around datumline

Post by jze »

Well, you are obviously a better soldier in this war of user-hostile FreeCAD, but that doesn't solve my problem for future projects. But thanks :-)
domad
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Posts: 2053
Joined: Mon Jun 22, 2020 12:16 pm

Re: Grooving around datumline

Post by domad »

Greetings to the Community!
you can also do this: just set the circumference to be subtracted from the center of the corner and operate with the subtractive sweep, indicating the external edges of the "T" as a path in succession
Attachments
V-vzpěra3.FCStd
(44.79 KiB) Downloaded 19 times
V-vzpěra2.png
V-vzpěra2.png (151.2 KiB) Viewed 803 times
drmacro
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Posts: 8870
Joined: Sun Mar 02, 2014 4:35 pm

Re: Grooving around datumline

Post by drmacro »

jze wrote: Sun Oct 24, 2021 12:59 pm Well, you are obviously a better soldier in this war of user-hostile FreeCAD, but that doesn't solve my problem for future projects. But thanks :-)
I don't get the user-hostile bit.

And, what does it not solve for future problems/projects?

For even more reference, your original approach with no dependency on generated geometry...as described in the links I've provided:
Attachments
V-vzpěra2-mac-2.FCStd
(107.51 KiB) Downloaded 13 times
Snip macro screenshot-84fcd4.png
Snip macro screenshot-84fcd4.png (96.55 KiB) Viewed 764 times
Star Trek II: The Wrath of Khan: Spock: "...His pattern indicates two-dimensional thinking."
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Shalmeneser
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Location: Fr

Re: Grooving around datumline

Post by Shalmeneser »

Sketch(000) is bad with T-vertex : impossible in PartDesign.
Should work symmetrical around YZ-plane
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