Japanese Crystals

(design: March 2004)

(Pictures of my creations can also be found in my BrickShelf folder)

1. The idea

People have been asking me if there will be a 4x4x4 Cube after the standard 3x3x3 Rubik Cube. I'd love to make one, but everyone who has already seen the interior of the 4x4x4 Cube will understand that it's not as easy as the 3x3x3 Cube. That's why I decided to build another puzzle, not necessarily one of my own collection. In an old book I found a full description of how to make my own Japanese Crystal.
I guess that the 3D-puzzles from Eric Harshbarger also inspired me to build this one.

2. Japanese Crystal with 51 pieces

	Left: the 51 pieces required to build the Japanese Crystal. Right: my pieces. The invisible parts are in different colours because I didn't have enough bricks; I got really desperate on the gray pieces (I had to use train-windows). I suggested to "borrow" bricks from the kids, but my wife disaggreed...
	Left: It looks great if all the pieces are in the same colour. Right: making the pieces was the easiest part. I found building instructions for this puzzle on the web, but even with these instructions it's still a difficult puzzle. The smaller versions are much easier... Below: the straightforward building technique results in some weak spots.

3. Japanese Crystal with 33 pieces

With a minor adjustment on the largest pieces, it is possible to make another (smaller) Japanese Crystal with 33 pieces.

	Left: the 33 pieces required to build the Japanese Crystal. Right: my pieces.
	Left: all the pieces in the same colour. Right: the completed puzzle.

4. Japanese Crystal with 19 pieces

With another minor adjustment on the largest pieces, it is possible to make another (smaller) Japanese Crystal with 19 pieces.

	Left: the 19 pieces required to build the Japanese Crystal. Right: my pieces.
	Left: all the pieces in the same colour. Right: the completed puzzle.

5. Smaller Japanese Crystals

With another minor adjustment on the largest pieces, it is possible to make yet another (smaller) Japanese Crystal with only 9 pieces.

	Left: the 9 pieces required to build the Japanese Crystal. Right: my pieces.
	Left: all the pieces in the same colour. Right: the completed puzzle.

Strictly mathematical it is even possible to make a Japanese Crystal with only 3 pieces (this one is known as "Cross Puzzle").

Left: virtual puzzle. Right: real puzzle.

6. SNOT-version

Because the straightforward building technique resulted in some weak spots, I decided to rebuild the Crystal using the SNOT-technique. Additional advantage: smooth surfaces on all sides make it look even better.

Left: the finished puzzle. Right: used pieces. Notice the smooth tiles on all sides; the bottom of LEGO elements is no longer visible. Right now, there is only one weak spot left: the key-piece with cilindrical center. This is justifiable since it is one of the smallest pieces.

Remarks:

• I didn't build the big Japanese Crystal with 51 pieces with this SNOT-technique because I don't have that many smooth tiles: it'll probably require more than thousand 2x2 smooth tiles.
• The choice of colours is merely the result of the amount of tiles currently in my supply.

More puzzles to come ??....