This is one of my favorite puzzles. I have a few others that I wish to build someday, but this one must come first. Many of my favorite puzzles came from my Paternal Grandfather, but this one I discovered at the Science Museum in Seattle, WA.
I have to admit that I tried to solve it several times while visiting the museum with my children, but eventually I saw someone solve it. So I discovered the solution without beating it myself, but it is a great challenge and I wish to share it with others.
Please utilize what you have on hand. Spare wood, 3D printer, cardboard, plastic, kite string: it doesn't matter.
I personally used some spare wood from my shop, 550 paracord, and some rings from my daughter's jewelry kit. Initially I was going to design and 3D print this project on a smaller scale, but instead it can be created in minutes with the right tools and some scrap lumber.
I used a miter saw and a drill, some screws, plastic rings and 550 paracord.
I will supply the dimensions of my project, but again you can change it up to accommodate for the supplies that you have on hand.
It can be hazardous to use the recommended tools. I am laughing as I write this only because I hurt myself tonight working on this project. I was wearing flip flops and dropped a drill on my foot drill bit side down. I tore myself up pretty good. Please use caution and wear proper foot wear at all times. Also hearing protection, gloves and other PPE.
Step 1: Parts and Pieces
I used a 1" x 7" base that is 19.5 inches long.
2 each Uprights 1" x 3" that are 12 inches long
1 top piece that is 1" x 3" and 18 inches long.
The center hole is cut with a spade bit that is 5/8". I tried a 1/2" spade bit initially, but I found it a bit tight for this puzzle.
I cut a 35" piece of paracord and used some 3/4 inch diameter rings to attach to the cord.
Step 2: Drill Holes and Tie Up the Rope and Rings
After you have cut your support pieces to length you can assemble them as seen in the photos. Drill your holes as recommended. A 5/8 inch hole near center on your top piece and a couple of holes down through the top piece that are large enough for your paracord to pass through. See photos as to placement and how to tie the rope.
Step 3: Object of the Game
There are two rings separated by a knot in the middle. Your goal is to pass one ring from one side over to the other side so that both rings are on the same side of the knot.
I am not going to post the solution with this instructable only because I am disappointed that I witnessed someone solve it before I could figure it out. I will post a video edit to this instructable on the last day of September 2016 showing the solution. If you feel you need the solution before that date please send me a comment and I will supply the answer.
Good luck and happy solving to you.
Step 4: Ring Puzzle Solution - Spoiler Alert
Do not watch the video if you want to solve on your own. Attached is a video of my son showing how to solve the ring puzzle.