Introduction: The One-Handed Knot Puzzle
This is a great little challenge puzzle that's perfect for all ages.
It consists of a small wooden ball on the end of a thin, pliable rope. The challenge is to successfully tie a knot in the rope with one hand, in one second or less.
Read on to see how to make this little puzzle, and for some tips on how to successfully perform the challenge.
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Step 1: Not As Easy As It Looks, Trust Me!
The GIF above demonstrates the challenge being performed.
Here's the video from which I created the GIF, in case you're curious. I've practiced this a lot, and have to admit that it's not as easy as it looks!
Step 2: Make One
The top photo shows the finished rope and ball.
There are only a few things you need to make this:
- thin and pliable rope*
- a 1-inch wooden craft ball
- paint if desired
*I tried a variety of ropes and cordages to make this, and nothing seemed to work as desired except for 3/16" synthetic clothesline which I found at a local superstore. (Paracord did not work--even with inner strands removed--and neither did some plasticky poly-braid and nylon stuff I tried.)
Step 3: Prepare the Line
Cut a 28" to 30" section of the clothesline and pull out the inner core. This will slide right out and can be discarded.
Tie a simple knot on one end of the line to keep it from fraying. This knot also gives you something to grip when trying to do the puzzle.
The non-knotted end will be glued into the wooden ball. To make this a little easier you may wish to fuse this end of the line, but it is not absolutely necessary.
To fuse the end, heat it up with a lighter for about 5 seconds until the frayed edge gets melty. Then quickly lick your thumb and finger and roll the melty end together into a point.
A fire-free option would be to simply roll a small bit of masking tape tightly around the non-knotted end. Trim as needed so any taped part will be hidden within the hole of the wooden ball.
Step 4: Paint and Glue
To paint the ball, I put it on a dowel and shot it with some spray paint. Any paint will work, though, or no paint at all. You could even just color it with a marker.
The non-knotted end of the line was glued into the hole in the craft ball with a little squirt of hot glue. Many kinds of glue would work; hot glue is just quicker.
The rope and ball is completed!
Now try to tie a knot in the rope with only one hand, in one second or less.
Go on, give it a try!
Step 5: Warning: Spoiler Alert!
The next step shows some specific tips on how to tie the knot.
If you'd rather not see the tips at this point, DO NOT READ THE LAST STEP.
I recommend making one and trying to figure it out on your own, which is much more fun than just being told how to do it.
Read on . . . if you must ;)
Step 6: Tips
So you're going to just read the tips, without even making one? Well now, where's the fun in that!?
You've been warned, so here it goes anyway . . .
The truth is, there's actually more than one way to cast a knot into the line.
My father-in-law swings the ball upward (the same motion as used for those old cup-and-ball toys), and then sort of throws a loop-lasso at it, through which the ball drops resulting in a knot. I can't seem to do it that way with any kind of repeated success.
The way I tie the knot is by gently tugging the line straight upward, and then whipping my hand downward turning my wrist over quickly to create a loop in the line. This loop is cast forcefully into the lower section of line, right above the ball. The loop swings under and around the ball, creating a knot.
This is all done in one quick motion. See the photos and notes for additional details.
If you make one, I'd love to hear about your experience in the comments. Have you seen this puzzle before, or do you know of another way to tie a one-handed knot?
As always, thoughts and feedback are encouraged.
Thank you for taking a look!