Magnetic Acrylic Rubik's Cube

Step 9 Drill and fill the 12 edge pieces

Now it starts to get fun. The edge pieces each join a pair of center face pieces, and eventually a pair of corners. This leaves 2 faces undrilled, and you just need to make sure these 2 faces connect along one edge.

Again, make sure your polarities work. The two sides that connect to edge pieces need to match - so both N or both S facing out, because a piece can get spun around and return flipped to the same position. Likewise, the corner-facing sides need to match outward-facing polarities, for the same reason. In my model, the edge piece facing sides are opposite in polarity to the corner piece facing sides. This is probably the best way, as I've found that my cube can combine very well in all manner of unexpected positions.

You'll note in the pics that you can now make a central 3x3 layer with 1 central piece, 4 center face pieces, and 4 edge pieces. You can also remove the central piece - something you can't do with a regular Rubik's Cube. Too, you can create the whole cube now, sans corner pieces.

The last pic shows the flexible nature of the layers of the magnetic cube. It's fun to twist it back and forth like taffy.