BUG? Fusion 360 locks up when combining two complex bodies

[mbainrot]

Hardware: MBP 2017 i7 16GB ram eGPU RX570

Addon used to generate helical gear (Massive kudos to developer!)

https://apps.autodesk.com/FUSION/en/Detail/HelpDoc?appId=9029586664984391977&appLang=en&os=Win64#inu...

Parameters to generate gear:

• Gear standard = Normal System
• Handedness = Right
• Helix Angle = 40 deg
• Pressure Angle = 20 deg
• Module = 2.5mm
• Teeth = 32
• Backlash = 0.3mm
• Gear Thickness = 5.0mm

Procedure

1. Create a gear
2. Create -> Mirror
   1. Select gear
   2. Select underside face (negative z)
3. Save your work
4. Modify -> Combine
   1. Target body = Top gear
   2. Tool bodies = Bottom gear
   3. Operation = Join
   4. New component = Unticked
   5. Keep tools = Unticked
5. Hit OK and then go and do your grocery shopping, Fusion 360 should be still there waiting for you with the spinning wheel of death

Workaround

1. Do all the above until you get to combine
2. Modify -> Combine
   1. Target body = Top gear
   2. Tool bodies = Bottom gear
   3. Operation = Join
   4. New Component = Ticked
   5. Keep Tools = Ticked
3. Don't go to the shops to do your shopping as F360 hasn't locked up 🙂

It appears something is having an unscheduled disassembly when it goes to delete the tool(s)

[jeff_strater]

@mbainrot, can you post the model in the state up until the combine?  It seems odd that the "keep tools" being off would cause a performance problem on its own, but we can check it out.

[mbainrot]

G'day Jeff

Please find attached 🙂 Thank you for the very fast response

post join was the copy of debugging for autodesk v2 that I made prior to attempting the operation.

I also have new component unticked, this morning I wasn't able to leave it for an hour like I did last time because I am busily working away making the most of my Queens Birthday long weekend 🙂

Ta,

Max

[jeff_strater]

Wow, that is very strange.  Thank you so much for sharing the model (I didn't have that add-in installed, so you saved a bit of time).  I see the same thing.  The strange thing for me is that Fusion seems to be stuck updating the graphics (if you can trust the progress bar in the lower right), but the graphics should not be a problem with a model this simple...

We will look into this.  I still don't get what the Keep Tools and/or the New Component could be doing that would slow things down so much...

[jeff_strater · Accepted solution]

One more strange piece of evidence, that I found totally accidentally.  I started the command to try it without "Keep Tools" checked, then, realizing that I wanted to save another design before potentially hanging Fusion, I switched to the other tab, and hit Save.  I'd forgotten that this would commit any command that is in progress.  When I went back to the window with your design, I saw that the Combine had succeeded.  So, somehow, not having that window active allows the Combine to complete.  This, actually, supports the idea that Fusion is somehow trying to update the scene in some way...  Bizarre...

filed as bug FUS-40748

[mbainrot]

Yay it's not just me 😄

Awesome thank you so much for putting time into it during the weekend 😄

Let me know if there is anything else I can do to help out

[jeff_strater]

@mbainrot, in our testing we found this to be a Mac-only bug.  Can you verify whether you are using a Mac?  Also, another workaround is to do a Modify->Compute All before the combine.  On my machine, this makes the combine, even with Keep Tools and New Component unchecked, work well.  Again, this one's a head-scratcher, but we are investigating.

Jeff

[mbainrot]

Yup I am running a Mac with eGPU