This puzzle is made from 6 identical pieces. Print or carve 6 of these and then figure out how to assemble them into the interlocking shape. Fun!!
Edit: I am using this as a calibration piece. Each one got better than the previous by tweaking one (or two) settings. And when you have 6 you get the complete puzzle. That way the repetitive calibration piece isn't a throw away.
There is also an "improved" version that may be more of a challenge to print with 2 unsupported faces.
Edit: The impoved .stl is now fixed using sketchup and netfab. It may work now.
This puzzle should scale up or down pretty well.
The assembled puzzle is a great desk ornament that stays together just long enough to be picked up and played with, but if one piece is pulled out too much the whole thing just falls apart. People's expressions should be priceless.
Edit: Google SketchUp file added.
Print this shape 6 times. X,Y, and Z dimensions should be in good registration with relation to each other. If your printer squashes or stretches very much it may cause you grief.
Assemble them in pairs with the 2 cuts toward the center. There are 2 pieces on each plane x, y, and z. Pairs should almost touch on their opposing corners. You may find it easier to fit one last piece in by making the whole thing more "slack" or fit all 6 pieces in "slack" positions and compress them into the shape all at once.
Edit: With this print the tolerances are very tight. that means the puzzle binds a bit (or a lot at first until some of the very rough pieces and strings are smoothed off.) It makes the puzzle even more challenging. But someone messing with it (wiggling 2 opposite pieces) will still be able to disassemble it very easily.
Edit: Another solution. A guy at my office grabbed 3 pieces in each hand. Assemble them into 2 halves of the shape and simply pressed the 2 halves together. Much easier... lol! But, it may require ambidexterity!
It all depends on your dexterity and patience.
The improved piece prints nice in PLA with a fan going to make the overhangs look good.