Combining Complex Geometries to Make a Mould/Cast - Fusion - Inventor Pro 2026 - EDU

[flia971]

I am trying to make a mould for a phone case with this bas-relief on the back which I built in Blender and Fusion, but when trying to make a negative of it using the 'combine' tool in to create the mould cavity it fails to generate. I suspect this is due to the complex geometry of the relief as the core of the mould (flip-side containing the hypothetical phone) generated with no issue. Ideally I would like to resolve this without sacrificing details from the relief. I'm also open to suggestions in Fusion or Blender and will go to those forums if prompted.

@flia971 The post title has been modified to include the products names and versions. - CGBenner

[CGBenner]

@flia971 

Welcome!  Are you able to share your file here for the experts to look at?  Also, what version of Inventor are you using?

[flia971]

Hi @CGBenner thank you for the welcome.
I am using Professional 2026 edu access (same with Fusion). Relevant files are here. They might be a bit of a mess, still getting to grips with Inventor.

[CGBenner]

@flia971 

Thank you for sharing!  It looks like a rather ambitious project... go big or go home, right!  Very cool if you can work it out.  We'd love ot see pics of the finished phone case!

[flia971 · Accepted solution]

Worked it out:

Rebuild geometry in blender - generates semi-planar open mesh

Decimate, remesh and close mesh in Fusion - positive volume STL file

Exaggerate relief axis in blender - exaggerates detail

Use bool tool to 'indent' the relief into a preloaded backplate - imprinted STL file

Close mesh in Fusion - repairs any zero-volume errors

Save as 2024 ipt and export the imprint to Inventor (preferred CAD software)
Mate backplate with the rest of cavity in Inventor, can't directly edit the backplate solid as it is too complex.

It's a bloody mission and I would still appreciate a simpler method, but this will suffice.