LED Cube 4x4x4 Frames

Had this LED Cube I build some time ago piloted by an Arduino.

Want to make a clean version, so I started by designing a frame to hold the LED's.

My first OpenSCAD script, tried to make it as parametric as possible.

This is far from a finished cube, but the grid already comes out nicely.

The electronics use a MAX 7219 chip, piloted by Arduino, only uses 3! ports from Arduino.