Why Are Fusion Dimensions 10X greater on imported .STL files?

[lorne01]

I tried out Fusion 360 this evening.  I found it odd that every .stl i imported had the dimensions wrong.  I verified with Sketchup, and sketch up has the dimensions right.  I have figured out that the dimensions are out by a factor of 10.  

Is there some setting or something that needs to be changed to get the proper dimensions?  

The picture attached is of a ruler that is verified in Sketchup to be 10mm (length of the green line, but in Fusion it is 97MM.  Does this mean all my prints will be 10X bigger than they should be and i will have to mentally adjust for the error?  

I would appreciate if you have any insight.  

[LarryC8PZ4]

Hi Phil,

While the object is a Mesh I do a "File/Save as STL". The resulting
file I pull into Simplify3d or Cura and it's 10x to big.

The workaround for this is to take the Mesh and turn off History,
Convert to Brep, then "File/Save as STL". The resulting file pulled
into Simplify3d is the correct size.

~Larry

[Phil.E]

@LarryC8PZ4 

First let me be clear: Fusion will "save as STL" using whatever units are currently displayed.

Assuming you mean "export" as STL, you should notice that this uses the same cloud translators that Upload uses. The cloud translators assume CM both for export and import.

Just curious, what is the advantage of using File > Export rather than right click on browser component and picking "Save As STL"? The latter is rather simple compared to your workaround.

[LarryC8PZ4]

Ah..  there is a couple of issues with the process, let me rephrase this to one part of the step.

Right click on a Mesh and Save as STL and the file will be 10x larger than your document size.

Right click on a BRep Body and Save as STL and the files will be the correct size.

I didn't test this with File/Export, but since it doesn't show anything about the units used for the cloud translation when you do the Export, I bet your right in that it will use CM and multiply the MM document by 10x.

[Phil.E]

Got it. At this point I'm just struggling to reproduce the effect.

In the image below, I've made a 10mm cube in brep and mesh. The document units are mm. 

Both cubes Save-as having "10 units" across. Inventor reads them correctly, so does Fusion.

• The image shows the mesh cube round trip. MeshBody1 was Save-As STL and then imported as MeshBody2
• Fusion offers to use mm by default.
• MeshBody2 is the same size as the MeshBody1

This tells me that the STL that comes from using Save-As STL is being produced with 10 units as the length of a side. Otherwise it would not re-import this way. Inventor correctly reads it too. 

So now I'm really curious, how you are getting scaled results using Save-As STL! Can you try the same workflow, just export a 10mm mesh cube and then re-insert it with mm units? Maybe I'm missing one of your key steps.

[Anonymous]

Thank you, that was making me crazy. 

Pete

[adamrw240]

Just wanted to let you guys know that this is still a problem in 2020.

I did this process:

1.Printed an stl. came out correct size

2. Opened in Fusion to import and edit 

    Units are in mm

    Tried open vs. import mesh

3. All dimensions are now 10x correct size.

Is it too much to ask to have Fusion assume all the dimensions are in mm considering everyone uses mm in stl files?

[etfrench]

Is it too much to ask people to start using a better file format like .stp instead of .stl?

[Anonymous]

I had the same issue but I discovered an easy work around that works for me. I wouldn't use the procedure below for critical parts but it works for wood cnc carvings. I use BLENDER (freeware) to rescale the STL files.

(1.) In BLENDER, import the STL file, this may take a few seconds if the file has a lot of polygons.

(2.) Once its loaded into BLENDER, select export STL.

(3.) In the export dialogue box there will be an item called 'Translation', I enter .10 for the scale.

(4.) Enter a unique file name, and save it.

Hope this helps.

[ralf.timmermans]

It is now 2020 and the bug is still there - any STL imported (importing STL's itself is a lot smoother now compared to paste actions that needed to be done though, credit where credit is due) into Fusion 360 is 10x larger and requires scaling.

Is there any update on when this bug will be resolved?

Kind regards,

Ralf

[Anonymous]

Seriously, this doesnt make any sense.

123D Design, a discontinued Autodesk program opens .stl files at the correct scale (but cant handle converting them to solids to be edited which is why i tried fusion), why is this not something that can be set and forget? why do i have to scale every .stl I open manually?

[Anonymous]

I have the same problem, thats why I found this thread.

A 32mm diameter OBJ ends up as 320mm wide. If there only was an option when uploading the file where you could specify the unit of the model, that would solve the problem if the unit is not present in the file.

Now you have to rescale each object imported somehow.

[laughingcreek · Accepted solution]

For you guys having trouble with the scale of your .stl upon import, please refer back to post 69 in this thread.  If you use the insert command instead of "open", you are presented with an opportunity to specify the correct units.  AD probably believes this is a viable workflow, so I wouldn't expect any changes to the current behavior. 

[Anonymous]

Yes I tried the Import function and it works fine. Open for OBJ files
should be disabled, since it works so poorly.

[Phil.E]

Use Insert > Mesh to pick units when importing mesh files.

[Anonymous]

Yes, that works great. But new user will keep on struggling with this, since the most intuitive thing to do is use "Open", like we all been raised to do. It would have been nice if when you Open a OBJ-file also could select (select-box) the unit used in that file, so that you get the right scale. 

[Phil.E]

Yes, we are well aware of this.

[Anonymous]

Yep, new user here and I'm already done with this software. Since I already spent the time drawing the part up, I was lucky enough to come across this string and used the steps to get my part out of Fusion. There are too many other good free programs out there. I'm not dealing with workarounds.

[etfrench]

Yes, I agree, having to select the units when inserting an STL requires far far too much effort.

[j.jackiewicz]

MARCH 2020 , all STL files imported to Fusion 360 are 10x larger for unknow reason. I read all this thread and there is no really quick and easy solution to fix it once for all !

my system is in "mm" AS EVERYONE ELSES.

MY FIX IS TO SELECT IMPORTED PART  AND GO TO "modify" , then "scale" then type scale: 0.1 ( 10 times less than it is now ) and DONE.

but this is step which should be done automatically by FUSION.

Autodesk SHAME on you!

[lichtzeichenanlage]

Unless STL files don't contain a unit, how should Fusion 360 do this?