Slicing your model

The general 3D printing workflow starts with a 3D model, exported as an .STL file, which is then put into software (Cura) that slices it into layers and outputs a GCODE file. GCODE is basically a set of instructions/toolpaths for the machines to follow.

​Cura is one of many applications (Simplify3D, Slic3r, MatterControl, etc) that slices your STL into layers and converts it to printer-specific GCODE.

Installing Cura 3

  1. Download the appropriate Cura version for your OS and the 'definitions' folder here: (access.caltech credentials required)
  2. Install Cura 3.
    • Windows: double-click the file WINDOWS - Ultimaker Cura-3.3.1-win64.exe, follow prompts
    • Mac: mount MACOS - Ultimaker Cura-3.3.1-Darwin.dmg, drag into Applications folder
    • Linux: save LINUX - Cura-3.3.1.AppImage to preferred location, make executable (In Terminal, chmod u+x [location saved]/LINUX - Cura-3.3.1.AppImage)
  3. Run Cura once and then close the program.
  4. Add our custom printer definitions ([printername].def.json files) to Cura's 'definitions' folder:
    • Windows: C:\Program Files\Ultimaker Cura 3.3.1\resources\definitions
    • Mac:  Applications > Ultimaker Cura > right click, 'Show Package Contents' > Contents > Resources > resources > definitions
    • Linux: Copy [printername].def.json files into ~/.local/share/cura/3.3.1/definitions (In Terminal, cp -a [location saved]/definitions/. ~/.local/share/cura/3.3.1/definitions)restart AppImage
  5. Run Cura.

Adding Printers to Cura 3

  1. Go to 'Settings' > 'Printer' > 'Add Printer...'
  2. Select each machine one by one under the category 'Caltech TechLab Printers'
  3. Add Printer

Using Cura 3

  1. Load your STL or OBJ file
  2. Manipulate your model as necessary (rotate, scale, etc)
    • NOTE: Our profiles have been preloaded with optimized settings designed to work well for most prints.  Please do not alter them until you familiarize yourself with how our printers operate.  
      • Recommended Default Settings:
        • Layer Height: 0.2mm
        • Wall Thickness: 0.8 mm
        • Infill Percentage: 20%
        • Print Temperature: 210° C
        • Bed Temperature: 60° C
        • Print Speed: 45 mm/s
  3. Click 'Prepare' (bottom right corner)
  4. 'Save to File/Save to Removable Drive' (save as GCODE)

    For a more thorough overview, please refer to the in-depth guides located at the Ultimaker Cura website: