Trouble Merging Surfaces

[Anonymous]

I provide 3D to 2D flattening software for soft goods manufacturers (i.e. bags and backpacks, furniture, marine canvas, shoes...  anyhing made from or covered in fabric)

I have a client who wants to use Fusion 360 to create "pattern pieces" from selections of surfaces that are to sewn together. He neatly organized the pieces by changing the surface appearances to different colors. (see picture.) The ideal, is to flatten these colored sections as one piece.   This is where he is running into the issue.

He uses the "Patch >Modify > Merge" tool in Fusion 360 to merge the three green surfaces into one green surface and here is what happens.

The shape completely changes.   I've tried this on a couple other projects and I get similar results.  I also had an Autodesk AE look at it and he can't see what we are doing wrong.

Summary:

- users build the 3d design in Fusion 

- they then need to merge 3D surfaces(not bodies) from the design into 3D pieces

- the merge tool will merge the surfaces but it changes the geometry 

Question:  is there a workflow that we can use to address this?

[ldevms]

Hi, CliffDude,

How have those surfaces been generated?  Did your client create a solid body for the couch, and then extract surfaces from that?

That will let me know what's going on. 

But in any case, the merge feature gets rid of the defining edges that there, which makes the group one large surface, which changes its shape.  The Stitch tool under "modify" in the Surface environment will do what you're looking for there. (screenshot below)

When I've used ExactFlat in the past, the goal has been to get one surface body, then right-click it in the browser, and choose "Save as STL" to then upload to EF.  I'm assuming that's the goal of your workflow as well?

Thanks,
Tanner

[Anonymous]

Hello Tanner

I have an IGES model of the couch that we are using for this example.  Can you help me validate the process with the Stitch command on this part?

Also, there is a new ExactFlat Publisher Plugin in the Fusion Exchange Apps store.

(https://apps.autodesk.com/FUSION/en/Detail/Index?id=appstore.exchange.autodesk.com%3aexactflatonline...

It will automatically convert the Fusion 360 model into an OBJ or STL file and upload it to the users instance of ExactFlat.  So there is no longer a need to manually SAVE AS STL.  Once we validate that the Stitch command works we can use the Plugin workflow.

Please let me know your thoughts

Thanks

Cliff

[TannerReid]

Hi, Cliff! I'll take a look today and see what's going on!

Hold tight.

Thanks!
Tanner

[Anonymous]

Hello Tanner

did you get a chance to look at the problem using the IGES file I provided?

Were you able to:
- combine the three faces into a single surface using the Stitch command
in Fusion 360
- validate that the geometry did not change when stitched
- export the the single surface to ExactFlat using the "ExactFlat
Publisher" Plugin

Thanks

Cliff Brown
VP Marketing - ExactFlat

[Anonymous]

Any update?  were you able to stich the three surface together into one and send to ExactFlat?

Thanks

[JamieGilchrist]

Hi CliffDude,

I was able to stitch together the surfaces using the Stitch command.  I tried the Merge, but Fusion errored out so not sure why you got the result you did.

I don't have an EF account so I wasn't able to upload.  If you can create an account that our UX team could have access to, I'd be more than happy to look at this for you.

I've attached my edited .f3d for you.

hope this helps.

[Anonymous]

Hello

unless I am looking at it wrong the model you provided is still three
separate faces.

[image: Inline image 1]

I created an ExactFlat Online account for you to test with.

First download the ExactFlat Publisher Plugin for Fusion from the Apps
Exchange store.

https://apps.autodesk.com/FUSION/en/Detail/Index?id=appstore.exchange.autodesk.com%3aexactflatonline...

Then go to http://efonline.exactflat.com/EFOnline/register.php to create an
account. There is no fee. I can't do it for you because it needs an email
address or you will not get the updates.


Then select the merge/stitched surface and click on the SendtoExactFlat icon


Then open exactflat online
http://efonline.exactflat.com/EFOnline/main_login.php
and you will see
your part in the
"select"menu. The process is outlines in this video.

https://www.youtube.com/watch?v=uRPBN3CeUpg

[Anonymous]

Hello 

unless I am looking at it wrong the model you provided is still three separate faces.

You can create an ExactFlat OnLine account.  The process is outlines in this video.

https://www.youtube.com/watch?v=uRPBN3CeUpg

1. First download the ExactFlat Publisher Plugin for Fusion from the Apps Exchange store.

https://apps.autodesk.com/FUSION/en/Detail/Index?id=appstore.exchange.autodesk.com%3aexactflatonline...

2. Then go to http://efonline.exactflat.com/EFOnline/register.php to create an account.  

There is no fee.  I can't do it for you because it needs an email address or you will not get the updates.

3. Then select the merge/stitched surface and click on the SendtoExactFlat icon

4. Then open exactflat online http://efonline.exactflat.com/EFOnline/main_login.php and you will see your part in the 
"select"menu.   

Please le tme know what you see when you complete the process.

thanks

[JamieGilchrist]

Hi CliffDude,

good talking with you today, and nice to hear from you.

So we have two parts to your issue at hand.

1.  The Workaround.

In order to get the result you wanted I had to take your stitched surface through Autodesk Meshmixer.

To do this I stitched together the surfaces I wanted for the flat pattern.  In this case the six surfaces you pointed out. And exported the resultant body as an STL

Once Stitched Fusion reads this as a single body with 3 faces and creating the STL honors the face priority of the body.

I save the STL to my local machine.

Open the saved STL in Meshmixer and export it from there.  Meshmixer reads the STL from Fusion as a single object.

The STL exported from Meshmixer (STL ASCII format in this case) was the one that came into Exact Flat without any issues.

2. Now the issue with the merging workflow you were initially having problems with.

I had some further discussions about our Merge tool in the Patch environment and it's current behavior is as designed; it has been designed to maintain the boundary of your selection, but to build the surface with minimum energy. This is why the tortured surface from your original.  When Fusion uses Merge it's priority is on the boundary of the selected entities and the underlying math of the surface will adjust to respect the boundary with the least amount of topology necessary to do so.  When the topology of your design changes the math necessary to describe it becomes increasingly complex, which is why we will distill the final shapes to be as simple as possible, in this example the three faces that made up the one body was to keep the underlying math as simple as possible.  Even in a seemingly simple design if the math gets too heavy then you, as the user, will pay a pretty hefty performance tax.  This is the balance we have struck.

I think the solution is to continue to work with you and the team at Exact Flat so we can get a smoother transition from Fusion into Exact Flat.

I'll send you a follow up email directly Cliff to talk about this.

hope this helps.