topic Re: Fusions .OBJ Import not working. in Fusion Support Forum

Fusions .OBJ Import not working.

RuvenBals — Wed, 18 Feb 2026 09:56:10 GMT

Hey,

I have been trying to import an .obj into fusion and no matter what .obj i try, fosion is never able to display it and gives a "negative voluem" error.

It cant be the .obj files I tried a lot at this point and they open fine in other programs.

I did even export blenders standard cube as .obj and fusion cant even open that.

Could someone give me confirmation that this isnt just me?

Thanks in advance.

Re: Fusions .OBJ Import not working.

TrippyLighting — Wed, 18 Feb 2026 12:21:08 GMT

Can you share that .obj and perhaps even the original Blender file?

I import files from Blender relatively often and they are substatially more complex than the default cube 😉

Re: Fusions .OBJ Import not working.

RuvenBals — Wed, 18 Feb 2026 16:03:37 GMT

Sure, thanks for the reply.

The skull is what im ultimatley trying to import. The cube is just blenders cube.

The screenshot shows what I see. Nothing and a non positive voleum warning.

Re: Fusions .OBJ Import not working.

TheCADWhisperer — Wed, 18 Feb 2026 16:17:33 GMT

@RuvenBals

No issue here.

Have you rebooted your computer and the issue persists?

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

Re: Fusions .OBJ Import not working.

TrippyLighting — Wed, 18 Feb 2026 16:15:48 GMT

Use Insert->Mesh, not File->Open.

I don't know what you want to do with this skull, but it is very low poly.

With a little bit of work in Blender, or Fusion (Its just way faster in Blender) you can eliminate all the triangles and make a quad mesh out of it. That can be converted into a T-Splie.

The result is not only vastly superior (non faceted!) geometry, you can modify with the T-Spline tools AND normal solid or surface modeling tools in Fusion.

If that interests you I can show you how to do that.

Re: Fusions .OBJ Import not working.

TrippyLighting — Wed, 18 Feb 2026 17:15:21 GMT

Here is this skull:

1. Cleaned up in Blender, meaning removed all the unnecessary triangles. This can actually not be done in Fusion as Fusion does not allow to convert fully triangulated models into T-Splines.

2 Inserted Mesh into Fusion

3. In Fusion, create a new form, select the mesh and convert from Quad Mesh to T-Spline:

4. Finished the form (it's now a solid body) , applied material and rendered:

Re: Fusions .OBJ Import not working.

RuvenBals — Wed, 18 Feb 2026 17:34:24 GMT

Thanks a lot!

So I tried quading the mesh too in blender and it still dosnt work.

The F3d has that quard skull I made.

Re: Fusions .OBJ Import not working.

TrippyLighting — Wed, 18 Feb 2026 17:48:58 GMT

@RuvenBals wrote:

So I tried quading the mesh too in blender and it still dosnt work.

How did you attempt to do this?

I first uses Faces -> tris to Quads.

That doesn't remove all the triangles and also in the process removes some edges that are correct while leaving others that should be removed.

I selected those edges that aren't needed and dissolved them. I also made some new edges with the knife tool between existing vertices to create proper edge flow.

Maybe 30 minutes of work.

The .obj is attached in zipped form. If you insert it with cm, then it should have the right dimensions (about 100mm tall)

Re: Fusions .OBJ Import not working.

RuvenBals — Wed, 18 Feb 2026 17:59:35 GMT

Thanks a lot! I just did the basic operation.
Even if i import your skull through insert mesh nothing shows.

I homed the view here. I did also try restarting my PC.

Re: Fusions .OBJ Import not working.

TrippyLighting — Wed, 18 Feb 2026 18:09:41 GMT

That is odd. The object shows in your browser. When you select the mesh object in the browser, do you see anything changing in the viewport?

Here is how this looks on my side. I have turned all grids off.

(view in My Videos)

Re: Fusions .OBJ Import not working.

RuvenBals — Wed, 18 Feb 2026 19:14:46 GMT

What Happens on my end.

Re: Fusions .OBJ Import not working.

TrippyLighting — Wed, 18 Feb 2026 19:51:34 GMT

@johnsonshiue Not sure this is a bug or perhaps graphics driver related. The mesh model is clearly inserted into the design, but is not visible in the viewport.

Re: Fusions .OBJ Import not working.

TheCADWhisperer — Wed, 18 Feb 2026 20:52:45 GMT

@TrippyLighting

When I open the file in Message 7 all I see is a line.

There must be something wrong in the OPs machine as the obj opens for both of us without the warning triangle.

Re: Fusions .OBJ Import not working.

RuvenBals — Thu, 19 Feb 2026 08:47:10 GMT

You guys are right it seems to be my PC.

The file opens perfectly fine on my labtop.

My workaround now is to open .obj's on my Labtop save the file and then open that file on my PC. A little anoying but I can atleast work on my PC that way.

Thanks a lot to @TrippyLighting for cleaning up the mesh for me. Ill show you what i make with it 😉

Re: Fusions .OBJ Import not working.

TrippyLighting — Thu, 19 Feb 2026 12:02:14 GMT

@RuvenBals wrote:

...
Thanks a lot to @TrippyLighting for cleaning up the mesh for me. Ill show you what i make with it 😉

Yes, that would be nice!

I created a 10 minute video of the editing process in Blender last night. It takes a bit of experience with Sub-D modeling to recognize whether or not the quad topology of a model can be recovered this way, but I've seen it often enough to warrant a little tutorial: