Jack Puzzle

Jack has created an assortment of puzzles. His projects include Duplex and RGB logic puzzles as well as Rigidity Sokoban puzzles designed using PuzzleScript.

The Jack Puzzle consists of six notched brass bars which interlock in such a manner as to form one unifying jack shape. Exactingly milled and weighing 1 lb, its craftsmanship cannot be faulted.

Professional Career

Jack enjoyed many interests outside of work, including hiking and camping with his family, exploring Finger Lakes, Adirondacks and Nova Scotia; creative writing; spending time with children, grandchildren and friends; as well as crossword puzzles and word search puzzles which occupied much of his free time.

Craighill’s Jack Puzzle is composed of six notched brass bars interlocked together into an “i-Jack” shape. Precisely milled and electropolished, this brain puzzle makes an attractive paperweight or desk object while offering true entertainment value. Participating in puzzle competitions or joining clubs provides another great way to advance these skills – an asset worth adding to your resume for professional advancement!

Personal Life

Jack had an irreverent sense of humor which he expressed through puzzles both directly and subtly. For instance, in Mechanic Overload!, players control Mac the human and CHI the robot to navigate their way through a factory of puzzles; other examples include Duplex: an level selector made using PuzzleScript; and Rigidity which shows rigid bodies using PuzzleScript.

One of his best-known puzzles was the Jack Puzzle, made up of six notched brass bars that interlock precisely to form a jack shape. Precisely milled by skilled machinists, it weighs one pound and can be challenging to disassemble and reassemble without handwritten assembly instructions being included with your purchase.