SOMA Crystal
SOMA News 21 july 2017

Build SOMA inside a box.

In October 2016 Paul Arzul wrote to me to tell about a special version of SOMA.
You all know how to make the SOMA 3x3x3 cube.
But how about assembling it when you are restricted to putting ALL the pieces through a hole shaped like the "T" piece.

Does it sound impossible - Well that's what this version is all about

The Box

The restricted soma
The problem is to try and assemble the cube inside a box with only a T opening.
If you do not rotate any pieces once they are inserted, then there is a unique solution.

The Box The Box

The Web tell us

"Restricted Soma" is designed by Martin Watson.
Size: 7 x 7 x 7 cm
The price is about US $31
Manufactured by Brian Young of Mr Puzzle Australia. Available for AU$45
Stamped "IPP35 Ottawa".
There is more than one solution with rotational moves.
However, there is a unique solution to the puzzle that does not use rotational moves.
Apart from the T section opening on the top face there are round holes in each of the other 5 sides.
They are large enough to allow you to manoeuvre pieces inside the box with your fingers, but just not quite large enough to let pieces come out of the box.
To get the pieces in and out there are some very unusual movement sequences but it will not be necessary to rotate the pieces.

For display it can be packed with the lacquered side of the black T piece to the outside making the box look complete.

To find the unique solution without rotational moves is very difficult.
A total of 21 moves is required, with the 4th piece alone needing 8.
A lot of fingering through the holes!

A printed solution showing the unique solution steps is included with the puzzle.

A Review is found on

Informed by Paul Arzul <>
Written by Thorleif Bundgaard <>

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