This game was given to me by my father 40 years ago. It took a little while to figure out then, I was young. Recently after being found after many years of hiding I discovered it was still a fun challenge. The object of the game is to get the nut on the b side of the toy to the a side of the toy. The nut does not fit through the center hole. I've challenged many adult friends to take the test and they failed. I wish, I could hide the answer until you were finished making it.
Step 1: Layout
Draw out the pattern on whatever you decide to use as a base. I chose a thin wood crate top just because it would be easy to cut with a carpenters knife and drill with a cordless drill. You could easily use cardboard, aluminum or plastic.
Step 2: The knot
Cut about 2.5 feet of the cord you have decided to use. Fold your cord in half and poke it through the center hole. Pull it through a couple of inches and then put the ends of the cord through the loop. You can now take both ends of your cord and push them through the front of your 1/4 side holes and tie then in a knot. Don't forget to put the nut on one end before tying it off. Now cut the excess cord off the ends.
Step 3: The solution
The Solution: Pull the nut up close to the hole. Notice the two cords coming out of the center hole.
grab the two cords mentioned earlier and pull them through the hole. Keep pulling until it pulls the loops through from the other side. Now you have 4 cords coming out of the middle hole. Now, look at the loop protruding out of the middle hole. Run the nut through this loop and to the other side.
Turn the puzzle over and repeat the process. Pull on all 4 cords all the way through until the knot on the other side comes back through. Pass the nut through the loop again.