Incorrect Scaling when Export OBJ

[GPastin]

I'm trying to export from F360, as I've done for the last 3 years, and today, all of a sudden, it's scaling my projects down to what appears to be a fraction of the size. 

I have a piece that's approx 2 inch by 2 inch in F360. I extrude it 18mm, and when I export it and open it in Slicer app (Cura), it's barely visible on the plate. What is causing this and is Autodesk fixing this issue? It occured with the forced update from the system. Worked fine 2 days ago.

Update: I opened the last project I worked on (March 26) and exported the same way, and it has the same issue. I, however, re-opened the .obj file I saved on March 26, and it imports fine! So it's something to do with exporting on F360...

exported project size

sizes supposed to be exported.

[TheCADWhisperer]

@GPastin 

Can you File>Export your *.f3d file to your local drive and then Attach it here to a Reply?

Also Attach your resulting mesh file for analysis.

[GPastin]

@TheCADWhisperer 

Lets see if this is what you're looking for. I typically export *.obj files, but here's the *.f3d file as requested.

As for the mesh file, .f3d isn't recognized on Ultimaker Cura, so how else can I get you the mesh file?  I usually export from Cura to *.gcode for my printer to read.

[TheCADWhisperer]

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@GPastin wrote:

I typically export *.obj files

As for the mesh file...

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*.obj is a mesh format file.

[TheCADWhisperer]

@GPastin 

First thing I notice is that your Sketch1 is not dimensioned and when I add the missing dimensions they do not make logical sense.

I observe that your document setting is mm units.

I right click on the Body and Save As Mesh to OJB as Millimeter Unit Type.

I then test the OBJ file by inserting the Mesh back into Fusion as Millimeter Unit Type...

The round trip with the OBJ Mesh matches the original geometry.

Attach you Mesh (*.obj) file here for diagnosis.

[GPastin]

Didn't realize .obj was mesh. ha. sorry for my ignorance. 

I've done nothing different in my process that I've been doing for 3 years. Once complete, File - Export - Select OBJ and that's it. Something happened in the back end to cause this issue after March 26. I'm hoping it's just something in the setting.

Thanks @TheCADWhisperer for helping and looking into it.

As I'm ready to sent this, I decided to follow your Right Click - Save as Mesh process. And it worked for me. I also went back to save it from File - Export and it worked again too.

So it appears something glitchy was happening in the back end and it appears to be fixed now. However the attached v1 is still exporting to be tiny. The Bear cutter today works fine. 

[TheCADWhisperer]

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@GPastin wrote:

However the attached v1 is still exporting to be tiny. 

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Mesh files are unitless so it is important to have document units set correctly and have export/import units set correctly at both ends.

Without the original v1 f3d file I cannot diagnose where you did not set the units correctly.

All of the experts here use Save as Mesh (faster and more options) rather than Export.

[GPastin]

The F3d file is the same file that was originally sent earlier. All I did was re-open it and re-export it. Nothing else changed from that perspective. I'll keep an eye out on my next project to see if the same issue arises.

[cmaterick]

I had the same issue with the latest update. I always previously used the Export functionality and selected the .obj option. With the latest update, it started exporting all of my projects scaled down to be tiny. Using "Save As Mesh" works fine. It seems pretty obvious that something changed with the .obj files now being done by the local translator instead of the cloud translator.

All that said, I went into one project and changed the active units as shown in a prior post - changed from Millimeter to Inch, clicked OK, opened again and changed Inch to Millimeter, ensured Set as Default was checked, and clicked OK. That seemed to trigger something, and the Export functionality started working to keep the .obj files at the correct scale. The fix applied to all of my projects. It's like they lost their active units and got them back when I adjusted one project and said to use that as the default.

I'm pretty positive what I did with changing and then changing back the active units on the single project was the solution. The only other thing I did was to use Save as Mesh as a test, and I don't think using that feature caused the Export functionality to work.

[vixeneyes28]

Currently also having this same problem. Just started yesterday in the middle of two projects. One Finished and exported fine to scale into Cura while the next one was massively smaller to the 2 inches it was supposed to be. Was having a few program crashes and in between the two projects Fusion did its update. And no won't export properly. I am not an expert at the system and use it simply. My question is where do i find this " Save as Mesh" option?

[cmaterick]

https://help.autodesk.com/view/fusion360/ENU/?guid=MESH-SAVE-AS-MESH

The export functionality also stopped working correctly for me again. Using "Save as Mesh" isn't a big deal, but it definitely seems like the export feature is broken and needs to be addressed. It's like it can't pick up the units from the design and defaults to something wrong.

[maechtigermietz]

Same problem here. Something happened in the last update.