Neal Spangler

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A replacement part modeled and 3D printed

I designed a replacement RC helicopter part in FreeCAD, exported an STL, sliced it in Cura and printed it on an Ender-3 V2 the same day.

RC helicopter part: model to print The part is modeled in FreeCAD, exported as an STL file, sliced in Cura into printer instructions, and printed on a Creality Ender-3 V2. FreeCAD's own .FCStd file does not open in Cura, so the STL export is the bridge. Model, export, slice, print FreeCAD model the part STL export Cura can't read .FCStd Cura slice to G-code Ender-3 V2 print the part Fusion 360 trial ended, so the model moved to free tools
From a model to a part in hand: design, export, slice, print.
1 dayfrom CAD model to printed part
$0software cost after the Fusion trial ended

The problem

My Autodesk Fusion 360 trial had just ended, and Cura, my slicer, won't open FreeCAD's native .FCStd files. I needed a free CAD tool and a clean path from the model to a printable file.

What I did

  • A FreeCAD model of the replacement part, after comparing free CAD tools to take over from Fusion 360.
  • An STL export from FreeCAD that Cura could slice, once it was clear Cura doesn't read the .FCStd format.
  • A physical replacement part printed on an Ender-3 V2 the same day as the design.

Photos

A Creality Ender-3 V2 3D printer laying down a small orange part on its print bed
Printing the replacement part on my Ender-3 V2, May 2025 (a still from my video).

View full size image

What I took from it

Cura would not open the FreeCAD project. Exporting it as an STL gave the slicer the file it needed, and I finished the part after the Fusion trial ended.

Home lab & side projects

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