Problem upgrading

[CrashedAgain]

OS: Ubuntu 20.04.3 LTS (MATE/mate)
Word size of FreeCAD: 64-bit
Version: 0.20.25645 (Git) AppImage
Build type: Release
Branch: master
Hash: 37d9757399b4c2ec30318eb88d7cd7c508246345
Python version: 3.9.7
Qt version: 5.12.9
Coin version: 4.0.0
OCC version: 7.5.2
Locale: English/Canada (en_CA)

Upgrading from 0.19.24276 multiple bugs appeared.

History - I have two computers, one of which is and older Lenovo at a remote location (resort cabin) with inadequate internet for direct upgrading. Having had considerable problems in the past with downgrading from a newer version to an older version, I make sure both are using the same versions of FC. I use Appimages since that is the only way I can upgrade the older computer. Recently I upgraded the main computer from 0.19.24276 to 0.20.25645. Everything seemed to be working OK so I upgraded the second computer also.

At first everything seemed OK, but then, after making a few edits, the objects in the file could no longer be joined into a union, although they seemed to render OK as individual parts. At first, they would "try" to show the fused objects but there would be errors - triangle shaped elements sticking out from the origin, etc. At this point the fusion would usually proceed properly if tried in the older 0.19 version. Then FC just stopped trying to join the shapes altogether and reported an error:

"13:12:29 <Part> ViewProviderExt.cpp(1356): Cannot compute Inventor representation for the shape of AirValveTest#Fusion"

At some point it also flashed an error that it was "unable to do a boolean operation on a non-solid" so it appears it was trying to do a boolean on a sketch. Sorry, was not able to capture the exact circumstances of that error.

Returning to the home computer, the problem is still there, so it does appear to have damaged the file in some way.
File is attached.
Both version 0.19 and 0.20 give the same error.
Reconstructing the file by copying the sketches and redoing the various revolves and extrusions does give a file which works properly.

While working in TechDraw on a different file, another problem occurred. On one of the views, I had several dimensions. I wanted to delete just one dimension but was unable to do it - deleting a single dimension removed ALL the dimensions from that view. Rebooting the computer seemed to correct the issue but very soon TD refused to delete any dimensions at all. It flashed a "failed to delete" message.
Sorry I do not have a sample of this problem.

Any ideas???

At the moment I am switching back to 0.19, hoping that the few files I have edited in 0.20 will survive the downgrade.

[Shalmeneser]

Try Part_CheckGeometry

[GeneFC]

Any ideas???

The screw is screwy in the shoulder bolt.

The sketch (028) has an extra line that is causing problems with the revolve.

Gene

[CrashedAgain]

@GeneFC Corrected the problem with the extra line (sketch 28). Corrected file attached.
Should have caught that earlier as that happens frequently with my approximation of screw threads if/when I shorten the screw.
Still unable to join the shapes, getting the same error, and it is unlikely that that is the cause of the problem because the error still occurs when I try to join only two or three of the shapes leaving the screw out of the fusion.

@Shalmeneser Part_CheckGeometry turns a number of errors, however I am unable to determine where the errors are because FC is not able to display the fused shapes so I cannot see them.

Also, Part_CheckGeometery on the individual shapes does not indicate any errors with the parts so they seem to be OK but FC is not able to make a proper fusion out of even two of the simplest shapes (disc and cover, for instance). (Screenshot attached)

BadFusion.png (121.43 KiB) Viewed 932 times

[CrashedAgain]

Process of trial and error - it appears that making almost any edit to sketch 27 (Cover sketch) will result in the fusion going proceeding correctly.

There doesn't appear to be anything wrong with any of the constraints in sketch 27, so it must be something related to to how the sketch was recalculated and saved when it was closed.

My real concern is how the error (whatever it was) came to be.

Since there don't appear to be other reports of problems with version 0.20, could it be a computer specific issue????
Failing hardware????
Incompatible with the operating system (unlikely, all my computers are running the same Ubuntu system).

Ideas? Suggestions?