Tuesday 25 November 2014

Rightangular Jam & Japanese Puzzle Box

These two puzzles were gifts from a puzzling friend of mine who lives in Japan. A big thank to Frederic Boucher (hope you are reading this)

The first is Rightangular Jam, designed by Hirokazu Iwasawa who entered it for the IPP24 Puzzle Design Competition. Iwasawa, as you may already know, gave the puzzling community such award winning puzzles as the ODD Puzzle and Square In The Bag.

Start Position


Constructed from MDF for the tray and three of the triangles (the blue triangle is wood), this version is made for the broader market. The Rightangular Jam is part of a series of three puzzles of the same genre (albeit different solutions and varying levels of difficulty). The other two are Rectangular Jam and Triangular Jam

The object is to get the blue triangle out of the tray through a narrow slit on one of the sides from the starting position as shown above. Its like a sliding block puzzle except here you are allowed to slide the pieces in any manner, diagonal etc, not just rectilinear, so long as none of the pieces are lifted off the tray

I found this one pretty challenging and took a good hour or so to figure out the moves. Its certainly harder than the Rectangular Jam. But a really nice and "elegant" solution; no force required. 

The second puzzle is a Japanese puzzle box or "14 Step Mame Yosegi Traditional Japanese Puzzle Box". For the history and more information about Japanese puzzle boxes, click here.  My puzzle box is "mame" (ie miniature; it measures only 4.3cm x 3.2cm x 2.7cm) with a Yosegi design.



In terms of difficulty, not difficult even though it has 14 steps. Once you discover the pattern of moves of the box, you are well on your way. Mine even came with a little "reward" in the form of a cute wooden cube (love the tiny criss-cross design!)




1 comment:

  1. HI Jerry,
    I am glad that you enjoyed these puzzles!
    In fact, Mr.Hiwasawa made three more puzzles in this series:
    Pentagon Jam, Hexangular Jam and 5 Yen coin in a Jam.
    -Frederic

    ReplyDelete