Fusion 360/Electronics 3D model joints constantly need redoing with unrelated changes

[warren_hawkins57R37]

As the title says joints and 3D PCBs have lots of issues. Changing something on the board can break the joints in an assembly that uses the board. Something should be done so that the joints can be relied upon. There should be constant references generated. Adding or removing holes or other parts should not break other mates.

We've also had two glitches that resulted in empty PCBs in 3D. We had to break the link and regenerate. This of course breaks the Mechanical assemblies in fusion which can take a significant amount of time to repair. This should be fixed. I should be able to completely regenerate a 3D PCB and not break anything in the mechanical model.

[ImDaveM]

yes, this is my biggest issue i have for long time, everytime i change something on the outline or geometry of the PCB, all or most or some of my joints go missing and have errors! i spend 90 percent of my time fixing up things due to bugs, this need fixing!

[lauri_barnhart]

Hello, @ImDaveM,

We are sorry to hear that you are still experiencing issues. We would like to suggest contacting Support for further assistance. They can help determine a possible workaround or if this is a bug, it can be reported to the appropriate team for triaging. You can always use the Autodesk Assistant on the support page to find answers or contact support.

Thank you for being a part of the community!

All the best,

Lauri | Community Manager

[ImDaveM]

this is a BUG because you don't seem to identify the HOLE as an object for proper reference, ( and i'm making the holes either with a reference sketch or simple circles on the 2D pcb design) attaching components say screws to a hole on the pcb, only references the SILK SCREEN circle, and when there are changes to the PCB, the whole pcb gets updated and all holes  are regenerated and the links to those circles are lost, from now on i suggest to have holes or openings with object ids ( these are internal, but would be cool to show the object id as well) , and at least for holes the centre axis is the reference for joints, and give each hole a object id, that was if a new hole is added or a hole is changed in size or position and existing joints will be maintained, except for holes that are deleted! and this should be noted in a clear list when the PCB is updated and there were joints, all the lost joints should be in a list that can be redone, currently looking for and editing existing joints is very messy. i spend far too much time fixing up errors instead of designing!!! 

[SallyYang]

Hi @ImDaveM,

Thanks for the additional details.

I tried reproducing this with a simple assembly using a 3D PCB, and in my case the joints did not break when adding holes in either the 3D PCB or the 2D PCB.

It would be helpful to understand what’s different in your workflow. Could you clarify:

• How the PCB is inserted into the assembly (e.g., creating linked PCB, derived PCB? inserting existing 3D PCB from the side panel)
• What types of joints you are using and what references they are attached to (e.g., hole edges, face, etc.)
• Whether the joints that fail are tied to specific features like holes or outlines

If possible, please share a sample assembly and electronics design. That will help us reproduce the issue and determine whether this is a workflow limitation or a potential bug.

Thanks!

[ImDaveM]

the joints break if i adjust the hole ( circles or PTH ) features in the PCB, if a circle or a hole moves that had a rigid joint then the reference for the hol eis lots, this happens all the time
and when this happens the joint highlights yellow in the timeline BUT the joint in the browser does not show the same yellow error, and the blue joint icon on the viewer stays blue, when is hould be yellow or red if it has a problem, i am constanlty re-doing my joints! i can only attach say fasteners to the silkscreen layer on the 3d pcb that is inserted.
if i just makes changes to the silk screen for example, the joints are fine. 

[ImDaveM]

[warren_hawkins57R37]

Adding/moving holes is sometimes ok and sometimes not ok. Also when things go wrong and we are forced to break the link to the 3D model to generate a new model, all of of the references are broken when the new model is inserted. This happens fairly often.

[SallyYang]

Hi @ImDaveM  @warren_hawkins57R37 ，

Thanks for sharing the additional information—it’s very helpful for reproducing the issue.
We’ll continue investigating based on the scenario you provided.

[ImDaveM]

Oh ok, did you move the hole in the pcb, the one with a jointed screw for example, and then update the 3D pcb and update the parent assy, as that' the time i get the joint error?

note i have been cleaning up a lot of errors, but i do need to fine tune my pcb design, like i need to move holes etc, 

you can view my link, and see if you get the same errors as i do.

try looking at my assy called "ASSY - PCA - Rear Output Panel" , if you see abig green body, you can turn that off, this is for later cutting for my enclosure, but the green body might hide the pcb components, this green body is not part of the errors, i had the errors all this time 

[SallyYang]

Hi @ImDaveM ,

Thanks for sharing the model with us.

The engineering team has reproduced the issue and logged a ticket (ID: FUS-242880) to track it.

From our investigation, we found that if the hole is moved in the 3D PCB workspace, the joints can persist. 

Additional information shared by the engineering team regarding this workaround:

"User can move the holes by editing them in 3D PCB and it will keep their joints intact in the assembly document. But if user pushes the 3D PCB back to 2D PCB to update it (check the DRC rules etc) and later again push 2D PCB back to 3D PCB, that moment they will start seeing this issue again. Because all the holes are getting recomputed."

That said, if you need to edit, add, or delete a hole, please follow this workflow:

• Make the changes in the 3D PCB workspace
• Update the assembly to preserve the joints
• Avoid pushing changes back to the 2D PCB, as this may cause the issue to reoccur

Could you please try this on your end and let us know if it works for you?

[ImDaveM]

hmm, so you get the same errors i get, meaning the holes or circles if moved in the 2D layout PCB workspace, that any joints will get errors and the component that was jointed will not move with it, BUT if the holes are moved in the 3D PCB workspace, then the components move ok and no errors? Is this what your saying?

OK well it is a bug BUT, i don't use the 3d PCB workspace to move the holes, i don't think i can actually? i need to move them or change them in the 2D layout PCB workspace as i have all the tools and coordinates of the holes, like X Y etc, its much easier to make changes in this way. and i ussly am making other minor adjustments at the same time like silk screen etc.

So i will try to move holes in 3D PCB, to see if that works, BUT i do need to update the 2D layout, so does it get errors here? when pushed back to 2D?

[warren_hawkins57R37]

There are more reasons to place holes in 2D than in 3D.  Often we don't place a hole as a hole by itself but rather the hole is a component from a library. The reason we do this is there are often keepouts, pads, silkscreens and countersinks included with the part. This functionality is not supported using the 3D method.

[ImDaveM]

yes, thats what i mean as well, in my case i was referring to hole or cutouts not associated with pcb components, (i think they update fine), 

[warren_hawkins57R37]

If I remember correctly the 3D sketch does not show holes included in components and also does not show anything on the milling layer.

[ImDaveM]

yes, i sometimes use the sketch when deriving outlines or i have complex cutouts and hole to deal with, it does not show everything related to all the holes or cutouts, it would be very good if the 3d sketch was treated and always included as part of the project file and all openings are included, maybe the ones for components can be locked in the 3d sketch? as need to deal with tracks ?? But its rather a confusing mess at the monent, and rather buggy! fusion could have the coolest pcb app but they don't do what is obviously needed! they seemd to have forgotten about PCB workspace..

[SallyYang]

Hi @ImDaveM  @warren_hawkins57R37 ，

Thanks for the details-this is very helpful.

Yes, your understanding is generally correct. Changes in the 2D PCB workspace can cause joints to lose their references when the 3D PCB geometry is regenerated.

Even if the holes are first edited in the 3D PCB and updated in the assembly, making further changes in the 2D PCB and pushing them back to 3D can still trigger a recompute, which may lead to the same issue if the joint references can no longer be resolved.

The 3D PCB workaround can help in some cases, but we understand it doesn’t fit well with your workflow, which relies on the 2D layout.

We’ve shared this issue (FUS-242880) with the development team for further investigation. Improving the integration between PCB and assembly is something we’re actively working on.

Thanks again for the feedback!

[ImDaveM]

thanks sally, this is good news! the main reason i use fusion is because of PCB and 3d modelling in the one app, its essential, that the 2 spaces work beautifully together, but there are lots of issues..

[ImDaveM]

Oh could you please put in a feature request for better highlighting of joints! change the colours n the browser to match the timeline, blue for ok, and yellow and red as well, that way we can see the errors as they appear, sometimes i never notice the colours in the timeline. and warnings saying there are downstream errors are very vague! it would be good to have a more comprehensive list of the components or parts affected by the errors. could you also put the joint number in the edit panel! and when hovering over a object in the timeline, please show all related components! its vaey hard to see what is going on, i waste too much time on bugs and fixing errors rather than engineering!

[SallyYang]

Thanks for the additional feedback, Dave.

I’ll share these improvement requests with the team working on joints, and they may reach out to you for more details.