Introduction: Simple Rope Puzzle
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Step 1: Tools/Materials
- Drill or Drill Press
- Drill Bits (1/4" and 3/8")
- Wood: 5" Long, 1" Wide, 1/8" to 3/4" Thick
- Rope: 1/8" Diameter x 26" Long
- Wood Ball: 1" Diameter
Step 2: Wood
I started with a 1/4" thick piece of scrap hardwood and cut it down to 5" long x 1" wide.
Step 3: Holes
Mark a center-line across the 1" dimension and then mark two locations 3/4" from the ends. Drill 3/8" diameter holes at these locations.
At this point, I cleaned up the holes and chamfered the sides with sandpaper.
Step 4: Ball
I used a 1" diameter wood ball. You can get these off Amazon, Ebay or a craft store. You will need enough space to feed two ropes through the hole. I started with a 1/4" diameter bit and then counterbored the other side with a 3/8" bit to capture the knot.
Step 5: Rope
Cut the rope to 26" to 28" long.
Step 6: Rope/Ball
Tie the rope together at the ends using a Double Sheet Bend Knot (see step 3 of my Buttonhole Puzzle for more details). Trim with scissors and melt the ends with a lighter. Bend the rope in half and feed the two pieces through the 1/4" hole. Pull the rope so that the knot is recessed into the counterbore. Fill the hole with glue or press a dowel into the space to prevent the rope from exiting the ball.
Step 7: Setup - Step 1
Feed rope through one of the holes in the wood block.
Step 8: Setup - Step 2
Feed rope through backside of second hole.
Step 9: Setup - Step 3
Feed rope back through first hole and then around ball. Pull loop back through hole. The puzzle is now set. Reverse the process to solve. If it isn't clear, watch the video.
Step 10: Pictures
Enjoy your puzzle. Thanks for reading.