Calibron 12 | The 1933 Edison Puzzle That Still Beats Most People

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$38.95

Add laser engraving (+$4.00)

Delivery and Shipping

All standard orders normally ship within 1 business day.

Custom orders normally ship within 2 business days.

Descripción

Calibron 12 is the legendary wooden packing puzzle designed in 1933 by Theodore Miller Edison, youngest son of Thomas Edison, MIT-trained physicist, holder of more than 80 U.S. patents, and founder of Calibron Industries in West Orange, New Jersey. Faithfully reproduced today by our family workshop in Hudson, Florida.

The puzzle is simple to explain and infamous to solve: arrange twelve wooden pieces to form a single square. There is only one correct solution. Most people who pick this up don't solve it on the first day. Many never do.

Laser-cut from ash, maple, walnut, and other fine hardwoods, with engraved markings for a precise fit. Includes the original 1933 instructions: arrange the twelve blocks to form a single large rectangle. Any rectangle, including the square, will do, provided every block is used.

Pieces: 12 unique wooden rectangles, laser-cut.
Difficulty: Expert. Widely considered one of the hardest wooden packing puzzles ever designed.
Material: Ash, maple, walnut, and other fine hardwoods, deeply laser-engraved.
Personalization: Laser-engraved names, dates, monograms, or a short message on the wood cover, up to 45 characters.
Ships unsolved. Printed solution sheet included for when you have exhausted every other idea.
Ships in one business day. Personalized orders ship in two.
Gift for: engineers, mathematicians, puzzle collectors, retirement gifts, STEM teachers, dads who want a serious challenge.

Recognition. The Calibron 12 puzzle was featured in The Mystery of the Calibron Twelve Block Puzzle, a research paper by George Miller and Nick Baxter presented at the Gathering 4 Gardner G4G12 conference in Atlanta, 2016. The paper traces Theodore Edison's original 1933 design and the rediscovery of its precise piece dimensions. It also documented that Edison issued the original Calibron in three versions, identical in their twelve pieces but each packed with a differently sized black spacer so the closed box never revealed the solution. David Janelle of our Hudson, Florida workshop is named in the paper's acknowledgements. Read the paper.

Want something harder still? Browse our expert wooden puzzles collection. Want something more approachable? Try the math puzzles collection.

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Product Specifications

Materials: Wood
Difficulty Level: Impossible
Age Range: Adults (18+ years)
Piece Count: 12
What's Included: Puzzle base (1), Puzzle pieces (12), Wood cover (1), Instructions and solution sheet (1)
Cognitive Benefits: Brain Training
Gift Occasions: Christmas, Birthday, Holidays, Mother's Day, Father's Day, Thank You and Appreciation
Personalization Available: Yes
Puzzle Type: Assembly, Dissection, Logic
Category: Brain Teaser Puzzle
Availability: In Stock

Personalize It!

Did you know we can add a custom laser engraving to every puzzle and game? Well, we can. Add a personal touch to your gift with a name or message.

Personalized laser engraving

a puzzle being laser engraved with personalized text by creative crafthouse

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Frequently Asked Questions

What is Calibron 12?

A handcrafted wooden brain teaser originally designed in 1933 by Theodore Edison. The goal is to fit 12 uniquely shaped pieces into a perfect square. There is only one correct solution.

Who designed Calibron 12?

Theodore Edison, son of Thomas Edison, in 1933. Creative Crafthouse produces this faithful reproduction by hand in Hudson, Florida.

How difficult is Calibron 12?

Expert. Considered one of the hardest puzzles ever designed.

What materials are used?

Each piece is hand-cut from ash, maple, walnut, and other fine hardwoods, with laser-engraved markings for a precise fit.

What is included with the puzzle?

Twelve uniquely shaped wooden pieces plus a printed solution guide for when you have exhausted every other idea.

Does Calibron 12 ship solved or unsolved?

Unsolved. Half the fun is putting it together.

Can I personalize Calibron 12?

Yes. We laser engrave up to 45 characters on the puzzle box at checkout.

Where is Calibron 12 made?

Handmade by Creative Crafthouse in our Hudson, Florida workshop.

Is Calibron 12 a good gift?

Yes. It is one of our most popular gifts for engineers, puzzle collectors, mathematicians, and serious puzzle solvers.

How fast do orders ship?

Standard orders typically ship within 1 business day. Personalized orders usually ship within 2 business days.

Who was Theodore Edison?

Theodore Miller Edison (1898-1992) was the youngest son of inventor Thomas Edison. MIT-trained physicist, holder of more than 80 U.S. patents (mostly in vibration control and damping), and founder of Calibron Industries in West Orange, New Jersey in 1931, the company through which he released the Calibron 12 puzzle in 1933.

Is Calibron 12 a good Father's Day gift?

Yes, especially for an engineer, a math-oriented dad, a tinkerer, or anyone who likes a real challenge that takes more than a single sitting. With laser engraving on the wood cover, it doubles as a keepsake from an inventor family's puzzle to your own.

Are these the original 1933 instructions?

Yes. The original Calibron 12 instructions read: arrange the twelve blocks to form a single large rectangle. Any rectangle, including the square, will do, provided every block is used. The square is the canonical target most solvers chase.