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.

3Dmodelto3Dprint.png
​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 v.15.04.2

We use an older version of Cura, as the new version is still being tested with our particular printers.  The software is available for Mac, Windows and Linux.  You can download Cura v.15.04.2 and our specific machine profiles here: https://caltech.box.com/v/librarytechlab3dp (access.caltech credentials required)

After installing, replace the pre-installed 'machine_profiles' folder with the one provided in the link above. 

You will be able to find the preset 'machine_profiles' folder on your computer here:

  • For Windows: | C:\Program Files (x86)\Cura_15.04.2\resources​
  • For Mac | Right click 'Cura' app > 'Show Package Contents' > Contents > Resources
  • For Linux ​|  Download the newest version and manually enter the settings found in the  machine_profiles folder (open as txt file) - OR - ​ Use a virtual machine and follow instructions above.

Once finished, open Cura and follow the 'Add A New Machine' wizard: 

  • Select 'Other', click Next
  • Select one of the 4 printers available, click Next, then Finish
  • Repeat for the other three printers on that list.  (From the menu, Machine > Add A New Machine)

Now, you're ready to select your printer and then load your STL file.  It's really important to select your printer before you load your STL, because the physical settings are different for each machine and GCODE sliced for one machine will not work for a different one.

Manipulating your model in Cura

You'll be able to manipulate the STL within Cura a bit, like rotate, scale, etc.  There are a few handy 'View Modes,' accessed by clicking the icon on the top right corner of the screen.  The ones I check most often are the Overhang Mode and the Layers Mode.

On Normal Mode, you will see the Rotate/Scale/Mirror icons on the bottom left.  In Layers Mode, if your model is missing faces or looks noticeably different from the Normal View, there's a good chance there's some sort of mesh error within the model.  If it looks good, then you're good to save as GCODE.

rotatescale.png

You'll also see settings on the left side of the program.   These settings are pre-loaded and optimized to give good results with our printers for most prints so we recommend beginning with those settings for your first print and then tweaking (or not) as you go along and observe any potential areas for improvement.

Saving your GCODE

Depending on the printer you selected, you will be saving your GCODE onto either a USB flash drive, SD card or microSD card. The TechLab has SD cards, microSD cards, USBs and adapters available if your laptop doesn't have the appropriate slots.

Bukito:  Save onto microSD card; rename file as [ AUTO0.G ] (make sure this is actually an extension change and that it doesn't save it as 'AUTO0.G.GCODE')
Craftbot Plus: Save onto USB flash drive; filename doesn't matter (you will be able to select your file from the LCD panel)
MAKEiT Pro M & L:  Save onto SD card; filename doesn't matter (you will be able to select your file from the LCD panel)