Tuesday, 1 December 2015

Pinned Wedge Key Puzzle

A rather long name but here's a fun (but not too difficult) puzzle I solved over the weekend. The Pinned Wedge Key Puzzle (PWKP) was Keith Winegar's IPP35 Exchange Puzzle to me in Ottawa, Canada this past August.

When I first saw his puzzle, I was reminded of two earlier puzzles with a similar design; Wil Strijbos' 4-Piece metal puzzle, and Hanayama's Cast Spiral. The object is to take apart the 4 pieces and then reassemble. 

Keith has designed a number of wedge key style puzzles in the past but he takes the PWKP design a couple of notches up.

Firstly in terms of construction, finish and quality...very good. The 4 jigsaw looking pieces are very precisely cut and all the outer edges and surfaces are beveled and smoothed. The puzzle is pretty hefty and solid with a size of 8.8cm x 8.8cm x 2.2cm and made of Black Walnut. 

What is different about the PWKP is that its made more difficult with a number of iron set screws inserted into the pieces. Besides the 4 pieces which "wedge" together to lock themselves, the screws serve as double reinforcement locking. The trick is to figure out how remove the screws and un-wedge the 4 pieces.

Another unusual thing is that the puzzle comes with two paper clips and a large thick rubber band. These are the only "tools" that a solver may use to help take apart the PWKP. No other external tools permitted!

It took me about 10 minutes to figure things out and separate the 4 pieces. Putting everything back was just the reverse.

Overall, a moderately challenging but great puzzle. Novices may take quite a while or even much longer, but for experienced puzzlers, it would be a relatively fast and fun solve. The PWKP is not commercially available but some of Keith's other designs and his earlier wedge key puzzle are available from PuzzleMaster.


  1. I agree this is a well-made puzzle and a good size. I found unlocking mine required a very specific technique which didn't seem to work about half the time. After a while I got better, but it was confusing when the same thing didn't always happen.

    The instructions give a different reassembly technique, but I found it easier simply to reverse the disassembly as you did.

    1. George, I think my own way of disassembly (and reassembly) works better (and pretty consistently) than the instructions, which I didn't quite fully understand,

  2. This comment has been removed by the author.


Related Posts Plugin for WordPress, Blogger...