Fusion 360 help - need to trim mirrors from dodge viper mesh before pulling t-spline box

It’s getting to be pinewood derby time, and this year I wanted to carve my son’s car on the x-carve.
He wants a dodge viper, so I looked for downloadable models, but most of what I’ve been able to find are STL or IGS files, with a body mesh.

I’ve imported one into Fusion 360, and watched a bunch of videos on pulling a t-spline box around a mesh, it works pretty well, but really gets thrown off my the side mirrors, and windshield wipers and wheel wells, etc.

I don’t care about that level of detail, but I haven’t been able to find any way to remove the mirrors before pulling the box around the mesh (can’t edit the mesh in fusion 360, from what I can see).
I’ve also tried fixing the form after pulling it, but it’s a mess of odd faces and so on and anything I do to it just seems to make it worse.

Anyone have any suggestions?


Can you import the STL or IGS as a solid model into Fusion 360 instead of a mesh? With Kubotek KeyCreator that’s the only way I can do any changes/editing.

@picengravertoo Well, it may be possible, but I don’t know how to do it, and haven’t found anything with all the google searches I’ve been doing.


I’m not familiar with Fusion 360, but with my cad/cam program, when I go to select the file for import, there is Options menu.

This opens up when I select Options.

I have not (yet?) found such an option in Fusion 360. I Do File->New Design from File, and from there I can select an IGES or STL file, but that’s it. It comes in as a mesh.

Now, there are ways to convert froma mesh to a b-rep, etc, but this mesh has nearly double the number of allowed triangles, so the convert fails.

The goggle-wisdom seems to be to pull a t-spline around the form, but of course, that doesn’t work here because there are portions of the mesh that I don’t want.


Hmm, also I just figured out that some of the strangeness in the pulled box is probably due to the fact that the bottom of the mesh is hollow, so it ends up snapping to the inside of the upper part of the mesh, so there are faces on top of faces…

I’m probably headed down a wrong path, but I haven’t figured out an alternative yet.


Looks like MeshMixer will let me make the changes I need.
Now I just have to figure out how to use it.