Binary Key II (2022)

DESIGNER: Pit Khiam Goh
RELEASE DATE: 3.21.2022
SIZE: 6" x 2.9"

Binary Key II is Pit Khiam Goh's two-dimensional interpretation of Bill Cutler's excellent "Binary Burr." The goal is to remove the bottom key from the frame by manipulating the internally sliding pieces. The solution requires 85 moves and is non-trivial.

Pit Khiam's description: "Binary Key II is a redesign of my Key Puzzle. The original puzzle was minimalist by design, but I felt some pieces could be changed to make them slide better. The key piece is now made shorter, and the number of rings has been increased to 5 instead of 4. The number of rings can be increased indefinitely due to the relation between the number of rings n and the number of moves Tn to solve the puzzle."

This is our first release of both Binary Key II and Tern Key since 2013. For this release we have modified the design with slightly thinner extruded acrylic middle and top layers for better operation. We also added a thin spacer layer to ensure smooth internal movement, and replaced the metal key pins with acrylic for more reliable press fitting and retention.

Precision cut from solid acrylic and painstakingly hand-assembled, Binary Key II has a nice weight and feel. It will not be confused with cheaper mass-produced take apart puzzles! Construction uses contrasting press-fit dowel pins to align the internals.

Here is an excellent blog review of Binary Key II. Another review of both Binary Key II and Tern Key may be found here.

Pair this with Tern Key for an ideal sample of grey-code style puzzles in your collection!

Previous Releases:

Customer Reviews

Based on 3 reviews
Fun and just challenging enough!

It’s a beautiful piece of acrylic, I love the serious-looking mechanical vibe. Took me about 25 minutes of tinkering to solve, 10 to reset. People really enjoy the feel of sliding pieces around and the material is resilient so it’s good for travel and sharing with friends! Came in a little black pouch wrapped in bubble wrap which I appreciate. This is not so easy that it feels like luck to solve but not so hard you want to rage quit— I found it be very relaxing! 5/5

Binary Key II

Amazing craftsmanship and the perfect size puzzle to enjoy anywhere! The travel of this puzzle is structured but very fulfilling once you get it down. Glad to have added it to my collection.

Stanley S.I.
Not yet had time to solve

Very nicely made puzzle, and a good design, I think. But I haven’t had time to really work with it and understand it. Got about 3 steps along, think I can get farther when I have the time to try. Seems nicely complicated

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