Editing (re-snapping) joint location in assembly crashes fusion.

[TrippyLighting]

I tried to edit/re-snap a joint location in an assembly. This invoked a warning in reference to a feature that is not part of that particular component/body.

A yellow highlight shows up on a feature in the timeline indicating a problem to recreate some geometry as indicated earlier in the warning message.

Upon just moving the mouse cursor over the highlighted timeline feature Fusion crashes yet again when attempting to troubleshoot a simple joint constraint situation.

I even deleted the acual joint constraints so ther would be no relation between the initially joined joint origins, butto no avail. I have yet agan hit a road block attemting to recreate an assembly that I started just Thursday last week. I recreated all components and assemblies following the guidelines in the Tips for Large Assemby management. My assembly may have roughly 30 components in its current state but will have 110+ if I ever get to finish it.

I apologize if this sounds rather frustrated, but it seems the one thing that I have been able to reliably and frequently do is crash Fusion 😕

I  inserted a link to the video on dropbox into  crash report

CER_105604905

[TrippyLighting]

I have tracked the problem down to the Stud, which I had earleir exported (save as) from another assembly. When doing so it appears that some of the  sketch and feature references broke.

For example the Revolve 1 feature mentioned it the video is the revolcve that creates the C-Clip grooves. The reference to the Axis to revolve the sketch around was lost.

That is yet another essential bug!

I've fixed these problem now in the Stud file, however, before doing so, these broken references were not highlihted and no waring was displayed and it looked like the component was fine.

That also is yet another bug!

This only becomes apparent when the Stud is inserted into another file. Then a number of warnings are displayed. Either this id not happen when I inserted the Stud into the LED lamp assembley or I may have overlooked it. Either way, I cannot fix it as any atempt to modift that component crashes Fusion, which is the actual root cause or the behavior described in the video.

I have not tried to delete the jonts/references of the stud to the other components and will try this next to see if I can edit it then.  

[innovatenate]

It sounds like you may have some projected geometry or some cross-component references that are being damaged when the joint is being edited and the component is moving. If possible, could you send me a public link to the design so I may look into the issue further?

A screencast recording or the steps you are using to reproduce the issue would be helpful as well. You can e-mail the public link to nathan.chandler@autodesk.com. 

How to Create a Public Link in Fusion 360:

Screencast

https://screencast.autodesk.com/

Let me know if you have any questions.

[innovatenate]

There's a command called Break Link available from the right click menu when you right click on projected sketch entities. You may consider using this command to break cross-component references in the sketch of the Stud component. Perhaps this will resolve the problem. 

I would still like to get a copy of the data set if possible to submit to development for further investigation. Fusion 360 should not crash!

Thank you in advance for your help.

Best Regards,

[TrippyLighting]

Hi Nathan,

I have sent an achived .f3d file to the email you provided and have shared the project with you. PLease read my second post. I am confident that the probelm is the mising sketch and feature references in the Stud component itself. I have fixed that in the single component file for the Stud, but at the moment I cannot touch the Stud in the LED lamp assembly file without Fusion crashing.

What I am referring to as sketch references are not crossrefereced from other components. I exported the Stud from another assembly and in doing so some of the referencess purely internal to the component were lost. E.g. the sketch for the C-Clip grooves was missing the reference to the plane it was sketched on. It was also missing the reference to the axis it was revolved around. There were a number of other equivalent problems with other sketches all within the single component Stud file which I have fixed. I can now insert the Stud into another file without invoking any warning messages.

Again, these are not Sketch entities projected from other parts of the Stud or any other geometry. 

Thanks for your imediate attention!

[innovatenate · Accepted solution]

I just sent you an e-mail with a couple of suggestions:

Lose the screw models with the helical threads actually modeled - this will greatly help with performance. Use the thread feature to simulate the threads on cylindrical faces with a bitmap.

To gain access to the problematic features that have lost references (found by running the compute all command), activate the problem component and right click on the body in the browser and select Find in Timeline. This will automatically Ungroup those features in the timeline and allow you access to the components. 

I will be submitting this to development for further review. Thank you for submitting this issue!

Take a look at the file and let me know if you have any other questions or problems.

Cheers,

[TrippyLighting]

The screws are downloaded from McMaster Carr in either STEP format or as a Solid Works part .sldprt. As such I cannot just edit the thread features away. I could in Soid Works and have done it there many times. These may result may a litte performance panelty but the geometry should otherwise be clean. I never had any problems with Mc Master Carr downloaded models in Solid Works or Alibre/Geomagic Design.
Another thing that comes to mind here is that I remeber watching a Fusion 360 demo that demonstrated feature recognition upon importing a part. That feature is not readily apparent to me in Fusion 360 Ultimate. If this would work then I could just eliminate the thread feature. Is feature recognition part of Ultimate ?

For future reference I have 25+ years of mechatronics engineering experience, roughly 10 years of Solid Works experience and for my private projects have used Alibre/Geomagic Design for the last 4 Years.

I will try what you suggested with force expanding the timeline item and let you know how it goes. Will not be until late tonight. One of my Sons is occupying my Mac right now playing WoW. Can't mess with that!
Thanks again for your immediate help. That makes frustrations much easier to deal with!

[TrippyLighting]

The workaround :

"...activate the problem component and right click on the body in the browser and select Find in Timeline. This will automatically Ungroup those features in the timeline and allow you access to the components."

Worked perfectly. I could repair the missing sketch references and corrctly join the components.

Thank you vey much.