Try-Cycle Mechanical

From designer Vaclav Obsivac, the six pieces of this puzzle are painstakingly handcrafted from four different types of wood. (Each puzzle is unique, so coloring may vary.) 

You may Try 3 (Tri) challenges: 
1 - Uni-Cycle: Simply form a cube (easy)
2 - Bi-Cycle: Each corner of the cube must be one single color (trickier)
3 - Tri-Cycle: The cube must have no identical color touching anywhere, not even diagonally or on an edge (a little more thought required...)