Hi, with this Instructable I want to show you how 3D print multicolored objects with a single extruder. To do this I wrote a OpenScad script, which allows us to do so. You can see the result in the image above

Step 1: How Does It Work?

The script allows you to cut a print into slices, which will be layered by the 3D printer, also it adds some support marks, which supports the printer. The marks center the print and lift the layers (slices). In between the layers/slices you have time to move the printer head and change the filament color or even the filament type. After restarting with the next slice the printer will automatically layer the slices.

Step 2: Requirements

3D printer with homing (usually printers do have homing)

OpenScad

Multiple filaments

The script: https://github.com/Jana-Marie/Rainbow-Space-Invader/blob/master/Rainbow.scad

A thing to print, as example we will use the Space Invader by User_4574 http://www.thingiverse.com/thing:35870

Step 3: Make & Print It

1. load your object into the script (look into the script for more information, it is commented there)

2. set your print level (slice) in the header of the script (e.g. 0.5 & 0 , this will create a level from 0 to 0.5, Image 1)

3. render your object with "F6" and export it as .stl

4. load your .stl into your slicer/g-code creator of your printer. Use following settings

-- Infill: 50%
-- z-axis lift: 3 mm (this will lift the z-axis during moves, to prevent the printer from crashing. It has to be at least as high as the print is)

5. Export the G-Code and print it with your favorite color

6. when the level is finished remove the skirt and the support blocks in the cornersbut leave the object itself ( Image 2 )

7. repeat from step 2 with new levels (now following 1 & 0.5 , this will the printer affect to build ontop of the first level, Image 3)

Step 4: Note

The settings from point 4 are very important to prevent your printer from crashing into the earlier slices! The printer has to lift the z-axis during moves.