Puzzle Cube
thingiverse
I copied this from a wooden puzzle with a caliper. I got the tolerances about right for assembly.
Download Model from thingiverse
With this file you will be able to print Puzzle Cube with your 3D printer. Click on the button and save the file on your computer to work, edit or customize your design. You can also find more 3D designs for printers on Puzzle Cube.