Introduction: Wood Ball - Metal Ring Rope Puzzle
This puzzle caught my eye because it is challenging and also a nice small wood working project. The goal is to move the ring from one ball to the other. The puzzle is a little more difficult to solve, even when the solution is shown in a video or still pictures. That means this puzzle will not be a quick look and then trashed. I have seen one family spend a good portion of one evening passing the puzzle around before and after the solution was given.
We'll start with showing a video of the solution to the puzzle. Then we'll cover complete construction details. At the end there is another solution using only photos.
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Step 1: Solving the Puzzle (Video)
Step 2: Materials Required
1. 4” x 4” x ¾” Wood for the base - Wood can be any 3/4" stock you have on hand.
2. Two 1 ½” wood balls - I bought a package of eight at Hobby Lobby. Most Hobby/craft stores would likely have an assortment. Actually the balls have nothing to do with the puzzle other than to make someone believe they have something to do with the solution. You could use any ornaments here or nothing at all!
3. Metal ring 1” i.d. – 1 ¼” o.d. - I found this at Menard's home improvement center. I think it was $.59 so it wasn't worth trying to make one.
4. 3 ½” of 3/8” wood dowel - All home improvement centers and most craft stores stock these.
5. 3” x 3” (approximate) x ¾” scrap wood for the wood ring - Any 3/4" stock you have on hand.
6. 24” of ¼” rope - Tight knit yet flexible. Some 1/4" ropes are a little too rigid.
7. Wood glue and/or Epoxy - Just about any glue or epoxy will work.
Step 3: - Tools Required
1. wood saw
4. Something to draw a 1 3/4" circle
5. Sand paper
6. Clamp or wood vise
Step 4: Making the Base Plate
Cut a 4” x 4” piece of ¾” piece of wood.
Drill the holes as shown. Each hole is 3/8” deep. Pay special attention to the 5/16” holes. Do NOT allow the drill point to peek through these holes because they have to form a pool for the glue or epoxy.
After the base plate is finished, you may want to consider adding any cosmetics desired such as sanding or routing the edges and paint/stain.
Step 5: Wooden Balls
The wood balls need to have a 5/16” hole drilled through them. The ¼” rope will pass through them and they must be able to slide up and down freely. Try to get as close to the center as possible. Use a wood clamp or wood vise to hold them while drilling. Provide a wood base under them while drilling to prevent them from splitting out.
If you can find 1 ¼” wood balls rather than 1 ½” it would make it look more like a possible solution. However the wood balls have nothing to do with this puzzle.You could just add any small ornaments in place of the wood balls. You also have the option to eliminate the balls all together.
This would be a good time to add cosmetics to the wood balls if desired (paint, stain, etc).
Step 6: Wood Ring Outline
The wood ring is made from any ¾ wood you have, including the stuff you made the wood base from. The steps for making the wood ring are as follows:
On a ¾” piece of wood, draw a rectangle, 2” x 2 ¼”. Do not cut anything until the directions specifically tell you to.
Draw a line 1/4” in from one of the 2” sides.
Step 7: Mark Wood Ring Center
Draw lines corner to corner on the 2” square. Make a mark for the center.
Step 8: Mark Mounting Hole
Make a mark 5/8” in from both sides on the bottom of the 1/4" side. Draw line from each 5/8” point to the side of the circle as shown.
Step 9: Drill Center Hole
Using a 1” spade bit, set the point in the center mark of the 1" hole and drill the hole in the center of the circle. Only drill about half way through the board. Now flip the board over. The tip of the spade bit should have poked through the other side. Using the small partial hole as a guide, finish drilling the hole. Be sure to continue drilling until you feel the drill pop through the other side. That should leave a hole with smooth outside edges on both sides. If you don’t continue drilling until it pops through, you will have to re-enter the hole to finish which will likely cause the drill bit to chatter causing a very rough surface for the inside of the ring.
Step 10: Trim to Outside Dimensions
Cut the outside dimensions (2" x 2 1/4").
Step 11: Drill 3/8" Mounting Hole
On the 3/4" bottom edge of the block, mark the midpoint between the 5/8" points (or 1" from either end). The wood should be ¾” thick so find the center width also, which should be 3/8”. Drill a 3/8” hole at this point, 3/8” deep. The hole is shown with dotted lines.
Step 12: Rough Trim to Final Dimensions
Now cut away all the excess. If you have a sanding machine of some kind, leave a little of the outside lines showing to use as a guide while sanding.
Step 13: Sand to Final Dimensions
Sand the wood ring down to the lines drawn. If you don't have a belt sander or disk sander you can cut the edges close with a scroll saw.
Step 14: Finish Sanding
Sand all the edges smooth. The inside edge should be as rounded as possible to allow the rope to easily slide through.
Step 15: Final Assembly
1. The photo shows the stuff you should have on hand at this point. Note that the wood ring and the dowel are stuck together only for a test fit on this photo. Also the ends of the rope have not been treated yet.
2. Glue the 3/8 wood dowel in the wood base. I would suggest that you use just a small dab of glue here. It is easy to make a mistake during assembly. Also, while solving the puzzle you may find your rope appears to be all tangled up. Experience shows that it would be nice to disassemble with just a little twist
3. Glue the wood ring on top of the wood dowel. The wood ring should be parallel to the back of the base.
4. Glue or epoxy one end of the rope into one of the 5/16” holes in the base. Make sure the rope is upright (sticking straight up out of the hole). If you use glue, be sure to wait until it dries sufficiently to hold.
5. Slide one ball onto the rope.
6. Thread the rope through the metal ring.
7. Thread the rope through the wood ring from behind. It's easy to make a mistake here!
8. Wrap the rope around the back side of the upright dowel. Again, it's easy to make a mistake here!
9. Now the rope needs to be inserted into the wood ring from the front.
10. Bring the rope back around to the front and slide it through ball #2.
11. The last step is to attach the end of the rope in the remaining hole. Before you do that, have someone hold it in place in the hole while you work the puzzle. It's easy to make a mistake with threading the rope or cutting the rope the wrong length. When it looks like everything is ok, epoxy or glue the end of the rope in place.
12. Now get out there and have some fun with this thing!
Step 16: Solving the Puzzle (photos)
1. Position the puzzle as shown in the first photo.
2. Lift the loop from behind the upright dowel over the top of the wood ring.
3. Center the loop around the two wood balls
4. Lift the metal ring up through the loop. Move it to the back of the wood ring. As you go through the remaining steps, try to keep the metal ring in back of the wood ring.
5. Now we need to work the loop up to the front of the wood ring opening. Pull on the loop from the back while lifting the loop from the front. You will have to shift the excess rope from the back to the front during this process.
6. When The loop is about half way up to the opening in the wood ring, grab the two outside ropes.
7. Lift both ropes to the top of the wood ring.
8. Pull straight up on both ropes to bring the loop tight against the wood ring opening. Again, you will have to work with the excess rope to get it to look like the photo. When you get to this point you can be pretty well assured you will be able to solve this puzzle.
9. Now we need to work the loop through the opening in the wood ring. Push the loop with one finger from the front and pull from the back with the other hand.
10. Pull the loop through the wood ring as far as you can. Again, you will have to shift the excess rope from one side to the other.
11. Push the metal ring through both loops.
12. Push all the excess rope back through the wood ring opening to the front side.
13. Pass the metal ring down through the loop onto the other ball.
14. Flip the loop back over the top of the wood ring to it's normal position.
15. Mission accomplished