A Coloured Cube - Fokenc170-1

Why this?

Following my project of producing 2d images in colour I am turning my attention to printing 3d coloured objects with an MMU2S. This model is a “proof of concept” to demonstrate the possibilities using the palette available using cmyk. It's name is a joke short for Non-tungible Foken (not very funny). 

The Maths

Imagine a unit cube with black at the origin, cyan at (1 0 0), yellow at (0 1 0) and magenta at (0 0 1). Now distribute those colours on the surface of the cube such that if the co-ordinates add up to less than 1 then the proportion of black is the amount needed to make the sum 1, with the other colours in proportion to their co-ordinate. Otherwise the distribution is just in proportion to the: x - cyan, y - yellow and z - magenta of that point on the surface.

The result is that e.g. the corner (1 0 1) will appear blue, (1 1 0) will appear green etc.

The Model

The model is made of cubes (pixels) of each colour interlinking to make the whole cube. Each edge is 170 pixels. The software that produces it has to distinguish between a corner (appears on 3 faces), an edge (2 faces)  and inner faces (1 face). Each corner is a single pixel selected at random if 2 or more colours have the same co-ordinate value (see blue above). Edges are comprised of 21 sets of 8 pixels. For each set the 8 pixel colours are calculated based on the mid-point of the set and then distributed in a random order. Inner faces are similar made up of 3 x 3 pixels. The reason for the name is that every time the software is run there is so much randomness I'll always (I haven't done the maths) get a different model.

Other sizes are available.

Printing

Load all the stl files. for settings use 0.35 for all extrusion widths and speed 1mm/s. No infill except for the inner box (check it is raised 0.4mm from the bed). If you don't have the right colours you should get a similar effect with red, green blue and white. For more detail on settings see my 2d prints.

Beware there over a 1,000 colour changes.

Full disclosure

The print went wrong as I nudged the SD card with 30 minutes to go and it killed the print! That's why one face looks bad,

Next Steps

My next print will be a 2d model using 8 colours: cymk rgb and white for a much bigger palette and gamut of colours, then I will be working general software for 3d colour printing