There are several different entries on this sight and many others on how to build led cubes. These cubes range from a novices 2x2x2 (eight leds) to the daunting task of the 8x8x8 (512 leds). Most people find that making the cubes one plane or (insert dimension here)x(insert dimension here) at a time is the standard way but, I have found it harder to solder the middle sections once you add the planes. Thus, this entry on a different method to reduce the frustration in making a Light Emitting Diode cube.
I will be walking through the 8x8x8 cube because this is a project that several people have tackled and many more would like to attempt in the future.
Jig: wood, cardboard, or any other material that will not melt, is sturdy and can have holes placed into it.
LEDs: color does not matter but, will effect the voltage going through the cube
Soldering materials: iron and solder
Step 1: Getting to know the LEDs
For a little background information on Leds and their properties please refer to the chart attached (below).
As you can see different LEDs have different attributes that may require you to chose some over others.
The other thing to consider is whether you are going to be using a common anode(+) or cathode(-) in your design
(the picture with the red led shows (a) as the Anode(+) and k as the Cathode(-)