Part Cross-section Attached to Wrong Body

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CopperGenie
Posts: 19
Joined: Wed Mar 16, 2022 12:44 am

Part Cross-section Attached to Wrong Body

Post by CopperGenie »

Hi there,

I have an issue with the "Part --> Cross-sections" tool.

I select my part (click twice), then select the "cross-sections" tool. This is what shows up:
Image
You can see that the splitting plane is "attached" to another body. When I click Apply as-is, it maps the cross-section to the non-selected body. When I try to move the plane over to my selected body and click Apply, I get the error message:

Code: Select all

11:20:21  <Part> ViewProviderExt.cpp(1270): Cannot compute Inventor representation for the shape of _0220116_structural_load_sensor_for_ISG#Fillet001_cs: Bnd_Box is void
I could find no way to get it "unattached" from this other body, even by deleting everything else in the file and trying again. I've tried in 0.20.1 and 0.20.2 and the issue is the same. I've attached the file for you to experiment with. Hopefully it's an easy fix, thanks in advance!

----

Code: Select all

OS: Windows 10 Version 2009
Word size of FreeCAD: 64-bit
Version: 0.20.2.29603 (Git)
Build type: Release
Branch: releases/FreeCAD-0-20
Hash: 930dd9a76203a3260b1e6256c70c1c3cad8c5cb8
Python 3.8.10, Qt 5.15.2, Coin 4.0.1, Vtk 8.2.0, OCC 7.6.3
Locale: English/United States (en_US)
Installed mods: 
  * A2plus 0.4.54b
  * Manipulator
Attachments
mystery part.FCStd
(357.38 KiB) Downloaded 23 times
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Shalmeneser
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Posts: 9475
Joined: Wed Dec 23, 2020 12:04 am
Location: Fr

Re: Part Cross-section Attached to Wrong Body

Post by Shalmeneser »

No problem in

Code: Select all

OS: Windows 10 Version 1809
Word size of FreeCAD: 64-bit
Version: 0.21.30922 (Git)
Build type: Release
Branch: master
Hash: 8ec1279ea8ee32a36fae683b42b5cfc5821734b5
Python 3.10.6, Qt 5.15.4, Coin 4.0.0, Vtk 9.1.0, OCC 7.6.3
Locale: French/France (fr_FR)
Installed mods: 
  * fasteners 0.4.55
  * fcgear 1.0.0
  * Manipulator 1.5.0
  * sheetmetal 0.2.61
User avatar
Shalmeneser
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Posts: 9475
Joined: Wed Dec 23, 2020 12:04 am
Location: Fr

Re: Part Cross-section Attached to Wrong Body

Post by Shalmeneser »

:idea:
Attachments
mystery part_SHALM.FCStd
(65.03 KiB) Downloaded 14 times
Capture d’écran 2023-03-20 185203.jpg
Capture d’écran 2023-03-20 185203.jpg (37.57 KiB) Viewed 957 times
CopperGenie
Posts: 19
Joined: Wed Mar 16, 2022 12:44 am

Re: Part Cross-section Attached to Wrong Body

Post by CopperGenie »

Shalmeneser wrote: Mon Mar 20, 2023 5:15 pm No problem in
Thank you. Do you have any suggestions of solutions within 0.20 that I could try? Or do I need to compile this experimental 0.21 version to get past this issue?
chrisb
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Posts: 53930
Joined: Tue Mar 17, 2015 9:14 am

Re: Part Cross-section Attached to Wrong Body

Post by chrisb »

CopperGenie wrote: Mon Mar 20, 2023 6:04 pm Do you have any suggestions of solutions within 0.20 that I could try? Or do I need to compile this experimental 0.21 version to get past this issue?
No need to compile (see Shalmeneser's link). These 0.21 versions have nothing experimental. They are very reliable, often more than the so called stable versions, because errors are first removed there. On very rare occasions this high quality can degrade, but such issues are usually fixed extremely fast.
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.
CopperGenie
Posts: 19
Joined: Wed Mar 16, 2022 12:44 am

Re: Part Cross-section Attached to Wrong Body

Post by CopperGenie »

chrisb wrote: Mon Mar 20, 2023 9:07 pm No need to compile (see Shalmeneser's link). These 0.21 versions have nothing experimental. They are very reliable, often more than the so called stable versions, because errors are first removed there. On very rare occasions this high quality can degrade, but such issues are usually fixed extremely fast.
Oh good to know, thanks!
CopperGenie
Posts: 19
Joined: Wed Mar 16, 2022 12:44 am

Re: Part Cross-section Attached to Wrong Body

Post by CopperGenie »

Shalmeneser wrote: Mon Mar 20, 2023 5:15 pm No problem in

Code: Select all

OS: Windows 10 Version 1809
Word size of FreeCAD: 64-bit
Version: 0.21.30922 (Git)
Build type: Release
Branch: master
Hash: 8ec1279ea8ee32a36fae683b42b5cfc5821734b5
Python 3.10.6, Qt 5.15.4, Coin 4.0.0, Vtk 9.1.0, OCC 7.6.3
Locale: French/France (fr_FR)
Installed mods: 
  * fasteners 0.4.55
  * fcgear 1.0.0
  * Manipulator 1.5.0
  * sheetmetal 0.2.61
I just tried the same process with the same file in 0.21 and I get the same result. Error code:

Code: Select all

16:59:17  <Part> ViewProviderExt.cpp(1268): Cannot compute Inventor representation for the shape of _0220116_structural_load_sensor_for_ISG#Body022_cs: Bnd_Box is void
Version info:

Code: Select all

OS: Windows 10 Version 2009
Word size of FreeCAD: 64-bit
Version: 0.21.0.32258 (Git)
Build type: Release
Branch: master
Hash: 0f4acc55beb66dcc9dfab442344c6286d6a2913e
Python 3.8.10, Qt 5.15.2, Coin 4.0.1, Vtk 8.2.0, OCC 7.6.3
Locale: English/United States (en_US)
Installed mods: 
  * A2plus 0.4.54b
  * Manipulator
This is interesting; maybe our processes are different. Here is my process:
1. Go to Part workbench
2. Double click the desired body to select it (Fillet001)
3. Go to Part dropdown menu and select Cross-sections

This is when I see the cross-section plane intersecting the wrong body.
chrisb
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Posts: 53930
Joined: Tue Mar 17, 2015 9:14 am

Re: Part Cross-section Attached to Wrong Body

Post by chrisb »

It is a bit cumbersome, but not really wrong.

Before starting, let's clear this: you should never apply a Part tool to a feature inside of a body. You should have selected the whole body either in the tree or by clicking three times in 3D view.

It is a problem of the Placement of the PartContainer. The cross-section rectangle appears always at the global (0,0,0), but it is applied correctly. You were mislead, because both parts look alike. You have moved rev2 to x= 90. If I change the shape of "body (no standoffs)" I still get the right cross section:
SnipScreenshot-00e081.png
SnipScreenshot-00e081.png (9.35 KiB) Viewed 700 times
The cross section is outside of rev2 and thus doesn't participate in its placement.

Move the crossection (selected in the image below) into the Part container rev2 and everything is as expected:
SnipScreenshot-6a99c1.png
SnipScreenshot-6a99c1.png (8.74 KiB) Viewed 700 times
Attachments
no_mystery_cb.FCStd
(290.79 KiB) Downloaded 14 times
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.
CopperGenie
Posts: 19
Joined: Wed Mar 16, 2022 12:44 am

Re: Part Cross-section Attached to Wrong Body

Post by CopperGenie »

chrisb wrote: Tue Mar 21, 2023 10:28 pm Move the crossection (selected in the image below) into the Part container rev2 and everything is as expected:
SnipScreenshot-6a99c1.png
I can differentiate between the two parts (one has an exposed csys in the file, making it easy to see which is which); the issue is the error I get when I try to perform the operation.

New process based on your recommendation:
1. Go to Part workbench
2. Select "body (no standoffs)001"
3. Go to Part dropdown menu and select Cross-sections
4. Move cross-section plane to intersect the body using the tools in the Guiding Plane box
5. Click Apply

Image

This is when I get the error I have posted:

Code: Select all

18:45:38  <Part> ViewProviderExt.cpp(1270): Cannot compute Inventor representation for the shape of _0220116_structural_load_sensor_for_ISG#Body022_cs: Bnd_Box is void
It sounds like we are "moving" the plane differently. Can you share the process you used to get to the state in the image you shared?
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