topic Re: Faulty STEP Export in Fusion Support Forum

Faulty STEP Export

wersy — Sun, 02 Aug 2026 16:18:01 GMT

Since I make my files available to the public, I export them as STEP files.
However, I wanted to make some changes to a fuselage part after the fact. For simplicity’s sake, I used the STEP file for this.
At some point, I happened to notice that the shell was defective.

That's really frustrating, because now I have to check all the files I've already converted for errors. There are now over 20 files, and it's almost impossible to find every error.

Now I also realize why the 3D printing slicer sometimes slices my STEP files incorrectly. So it’s quite possible that the problem isn’t the slicer, but rather the STEP file from Fusion.
The STEP format isn’t just a very important exchange format; it’s also recommended for better slicing.

It’s very frustrating that I can’t rely on Fusion to export files without issues.

Re: Faulty STEP Export

jhackney1972 — Sun, 02 Aug 2026 17:19:08 GMT

I was wondering if you would like to move your post to the Fusion Support Forum. I believe it belongs there for better support from Autodesk. Let me know, I can move it for you.

Re: Faulty STEP Export

wersy — Sun, 02 Aug 2026 18:49:43 GMT

@jhackney1972 schrieb:
I was wondering if you would like to move your post to the Fusion Support Forum. I believe it belongs there for better support from Autodesk. Let me know, I can move it for you.

Thank you, I would be very grateful if you would do that for me.

Re: Faulty STEP Export

JamesMcMullen — Tue, 04 Aug 2026 14:46:09 GMT

Is it possible to know what viewer you are viewing the STEP file? The reason I asked is that I uploaded both files provided into Fusion and the STEP file looked like the original file. I exported the original file into another STEP file and did the test again with success.

Re: Faulty STEP Export

TheCADWhisperer — Tue, 04 Aug 2026 19:01:27 GMT

@wersy @JamesMcMullen

When I run Quality Check on both files posted - I get indication of issues with 2 faces.

(view in My Videos)

Re: Faulty STEP Export

pkomatlapalli — Fri, 07 Aug 2026 11:09:06 GMT

Hi @wersy ,

Did you get the chance to look into JamesMcMullen follow-up question or still you need help from the community,
If you were able to resolve it, could you please let us know what solution or workaround worked for you?

If not, please feel free to share an update, and the community will be happy to assist further.

Thank you for your time, and we look forward to hearing from you.

Re: Faulty STEP Export

wersy — Fri, 07 Aug 2026 20:00:35 GMT

Thanks @TheCADWhisperer for checking it out.
It can be repaired, but it’s still broken.
I started working on the Minibat in 2019. The Minibat was originally supposed to be built with a wingspan of 3 meters. Later, I scaled it down to 50%. In the first version, this tail section was a completely solid object that was simply printed hollow.
Now the part had to be shelled because some internal structures were required due to the installation of a tail motor.

Maybe I'll be able to figure out at which stage the fault occurred.

This is the Minbat

Re: Faulty STEP Export

wersy — Fri, 07 Aug 2026 20:04:26 GMT

@JamesMcMullen schrieb:
Is it possible to know what viewer you are viewing the STEP file? The reason I asked is that I uploaded both files provided into Fusion and the STEP file looked like the original file. I exported the original file into another STEP file and did the test again with success.

Can you please upload your exported STEP file?

Betreff: Faulty STEP Export

wersy — Sat, 08 Aug 2026 14:10:34 GMT

I've now figured out that the shell is causing the problem right from the start.

The original solid

Shell

Issue

Now we ran a test using SolidEdge.
The part was imported into SolidEdge as a STEP file and hollowed out there.
The STEP file exported from it contains no errors.

Re: Faulty STEP Export

JamesMcMullen — Wed, 12 Aug 2026 12:30:36 GMT

I am glad you were able to get this squared away.

Re: Faulty STEP Export

wersy — Thu, 13 Aug 2026 12:34:12 GMT

@JamesMcMullen schrieb:
I am glad you were able to get this squared away.

It has now been proven that a different program exports the same part without errors.
However, the problem with Fusion remains.
This would mean, just to be on the safe side, carefully checking every STEP export from Fusion. And if it contains errors, using a different program, such as SolidEdge.

Re: Faulty STEP Export

wersy — Thu, 13 Aug 2026 13:20:59 GMT

I'm sorry, but this problem cannot be considered solved.
Using a program other than Fusion is not a solution.
I had hoped the problem would be reported to the developers.

Thanks for bringing this to our attention. We're investig...

Closed-Loop-Bot — Fri, 14 Aug 2026 20:37:34 GMT

Thanks for bringing this to our attention. We're investigating the issue, and you can reference ticket FUS-269082 when communicating with Autodesk to find out more. Once the status of this will change, there will be a follow-up forum post made.

Re: Faulty STEP Export

JamesMcMullen — Fri, 14 Aug 2026 20:48:46 GMT

Thanks for attaching the video. I was able to get a better understanding of the issue and get a ticket created for you.