Drawing opens fine in 0.18 but crashes in 0.19

[bowcoastie]

Hello All,
I drew a simple exercise drawing in version 0.18 but when I went to open it in 0.19 it crashed. So I went and downloaded the latest version of 0.19 and tried again. Same results. I then simplified the drawing by eliminating the last step in the drawing and this time 0.19 opened it but with the following errors:

21:26:18 AttachEngine3D::calculateAttachedPlacement:InertialCS: inertia tensor has axis of symmetry. Second and third axes of inertia are undefined.
21:26:18 AttachEngine3D::calculateAttachedPlacement:InertialCS: inertia tensor has axis of symmetry. Second and third axes of inertia are undefined.

When I hover over the sketch that shows the errors I see "Error, Internal Name: Sketch001" and "Error, Internal Name: Sketch002"in the command line.

Attached is the sketch in question. Is this a bug?

I sincerely appreciate any guidance.

My version of 0.18:
OS: Windows 10
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.18.16131 (Git)
Build type: Release
Branch: releases/FreeCAD-0-18
Hash: 3129ae4296e40ed20e7b3d460b86e6969acbe1c3
Python version: 3.6.6
Qt version: 5.6.2
Coin version: 4.0.0a
OCC version: 7.3.0
Locale: English/UnitedStates (en_US)

My version of 0.19:
OS: Windows 10 (10.0)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.22960 (Git)
Build type: Release
Branch: master
Hash: c5a4b01d2e4218bcc0eb6650337650a6c65ef0e4
Python version: 3.8.6
Qt version: 5.12.5
Coin version: 4.0.0
OCC version: 7.4.0
Locale: English/United States (en_US)

[bowcoastie]

In order to further figure out what is going on, I redrew the part in 0.19 in exactly the same order of operations as the version 0.18 and it shows no errors. I looked at the drawing from 0.18 and it shows errors now but only after I looked at each sketch individually but the drawing was overall still stable. I redrew the drawing in vs 0.18 using the same steps as before and now I don't see any errors.

Is there any way to know how I introduced the errors and what the error messages mean?

Thank you for any assistance.

[kisolre]

No crash here:

OS: Windows 8.1 (6.3)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.23133 (Git)
Build type: Release
Branch: master
Hash: c582e8a0857d42709b74f3246e5604e09fd22320
Python version: 3.6.8
Qt version: 5.12.1
Coin version: 4.0.0a
OCC version: 7.3.0
Locale: Bulgarian/Bulgaria (bg_BG)

Might be the different OCC version which generates geometry in different order resulting in weird edges for the fillets due to topological naming problem which in turn makes OCC kernel to crash.

[chrisb]

Might be the different OCC version which generates geometry

That's indeed the case. Already the support for Sketch001 has changed and the model breaks. Have a look at this page, especially the paragraph about creating stable models.

[bowcoastie]

Hello ChrisB and Kisolre,
Thank you both so much for your replies. It appears that the trouble started with changing the color of the part in 2 different places. Is there a mechanism to look at the errors in a part? No knowing exactly what causes an error is frustrating.

[chrisb]

It is probably not the color setting. That only caused the recompute and that revealed the error. You should redirect the errors to ReportView in the Preferences->General->Output. Then errors are shown there, or some are shown in the tree with an error icon (exclamation mark) and show the error when you hover over them.

[bowcoastie]

Hello Chris,b, Thank you for the info.