How to do the pencil and buttonhole trick

The pencil and buttonhole trick is a pocket puzzle: a pencil with a loop of string shorter than itself ends up locked onto someone’s buttonhole, and only you can take it off. The secret is to pull the cloth through the loop, not the pencil. You can make one in ten minutes and learn it in five.

What does the audience see?

You show a pencil with a small loop of string tied near the top. The loop is clearly shorter than the pencil, so it can’t slip over the end. A moment later the pencil is hanging from a friend’s shirt, locked through their buttonhole. They are welcome to take it off without cutting or untying the string. Most people can’t, and when you take it off for them it looks just as impossible.

Strictly speaking it is a puzzle rather than a trick, but it gets the same reaction, and it costs almost nothing to make.

What do you need?

• A new pencil, ideally one with a metal band and eraser.
• A piece of thin string.
• A small drill or a hand drill, used by or with an adult.
• A shirt or jacket with a buttonhole big enough for the pencil to pass through.

How do you make the pencil?

1. Drill the hole. Make a small hole through the pencil just under the metal band at the top.
2. Tie the loop. Thread the string through the hole and knot it into a loop that is 1 to 2 cm shorter than the pencil.
3. Test the length. Check that the loop can’t slide over the point. If it can, tie it shorter.

How do you put it on a buttonhole?

1. Open the loop. Hold the pencil and lay the loop over the buttonhole.
2. Pull the cloth through. Pinch the buttonhole and the fabric around it and pull them up through the loop.
3. Feed the pencil. When enough cloth is through the loop, put the tip of the pencil into the buttonhole.
4. Pull it through. Draw the pencil all the way through the buttonhole. Let the cloth go, and the loop closes around the buttonhole like a knot.

Do it slowly the first few times on your own shirt. Once you can see what the cloth is doing, it becomes quick and smooth.

How do you take it off again?

Do the same steps in reverse order. Gather the fabric around the buttonhole and pull it up, while pulling the loop the other way. Then draw the pencil’s point back out of the buttonhole.

One tip from puzzle makers: you never need to get the loop over the pencil. You only need to get the end of the pencil out of the buttonhole. People who try to force the string over the point are working on the wrong problem.

Where does the puzzle come from?

Puzzle historians Jerry Slocum and Jack Botermans tell a story that the puzzle maker Sam Loyd made a version, a small stick on a loop of cord, as a promotional puzzle for the New York Life Insurance Company. We can’t confirm the details of that story, so treat it as a story.

Based on our research, the earliest printed version we’ve found is Henry Ernest Dudeney’s “Releasing the Stick”, problem 349 in Puzzles and Curious Problems (1931). It has appeared in many puzzle books since.

How do you make it more fun?

• Make it a challenge. Put the pencil on a friend and give them a minute to get it off. The longer they struggle, the better your release looks.
• Do it slowly. A slow, calm removal looks more mysterious than a fast one.
• Make spares. They cost almost nothing, so you can hand them out at a scout meeting or in a classroom.

What are the common mistakes?

• A loop that’s too long. If the loop can slip over the pencil, there’s no puzzle. Keep it shorter than the pencil.
• A loop that’s too short. If there isn’t enough string, you can’t pull the cloth through. A loop only a little shorter than the pencil works best.
• A small buttonhole. The pencil has to pass through it. Test the shirt first.
• Pulling hard. If it sticks, stop, go back a step and gather more cloth. Forcing it can damage the buttonhole.

If you enjoy string and rope tricks, try the cut and restored rope next.

What helps you take it further?

• Mathematical Recreations and Essays by W. W. Rouse Ball, free from our public-domain library. Its chapters include string figures from around the world and a dozen string tricks.
• Rope with Hole 2.0 by Ding Ding. A string tied through one hole in a playing card jumps to the hole at the other end, then to the centre hole. It is a fun gimmick to make and easy to perform, with streaming instructions.
• Deluxe Ring and Rope by TCC. A metal ring penetrates, links and unlinks from a silk ribbon, with a video tutorial from basic moves to advanced handling, and it can be examined before and after.

Frequently asked questions