This is my take on the classic wooden snake puzzle. Purchased ones generally range in size from 2" cubed down to key chain size. This one is 4.5" cubed. Although time-consuming and somewhat mind numbing, it wasn't very challenging to build. However, you will need to pay attention to the build and assembly instructions.
Drawings & Build Instructions: https://www.instructables.com/id/Wooden-Snake-Puzzle