The Grandfather of 6x6x6
A 50th anniversary
The exchange puzzle which I present this time is in a way a
historical one. Although it is well known in a certain way by the
book of Van Delft and Botermans, Creative Puzzles of the World,
it has never been available publicly. The French firm of Arjeu
has once traded another 6x6x6 which had errors in it. They
misread the drawing in the book, and they even had the
impertinence to include a drawing which was an exact copy of my
own drawing with the accompanying text: "Reproduction Interdite".
They never mentioned my name or had my permission to bring out
Let me shortly tell something about the history of this design. I
always have been fascinated by wooden bars, seemingly penetrating
each other in an impossible way and the maximum complexity which
would be reasonably makeable was 6x6x6. This all happened around
1951. For two years I have turned it around in my brain until I
found a nice solution. I always say: you have to be able to draw
it on the inside of your forehead. At that time a drawing was
never made. Drawings only can depict static things; they cannot
be changed live.
So at last I took a long bar of beach wood and started to saw the
pieces. The final drawing only was made two years after the
creation of the puzzle! That original single copy was initially
exchanged with another puzzle from Stewart Coffin, when I visited
him in 1975 during a sabbatical at the IBM labs in Yorktown
Heights. The Coffin puzzles were very popular at that time and
for the first time some people succeeded in solving my puzzle.
There were no computer programs such as Bill Cutler's in those
days! Designing and solving was really brain work. This beach
wood original is now in possession of Jerry Slocum. For myself I
had another copy being made for me in aluminium and has been the
only copy for years.
In the course of the years and with the help of computer programs
improvements have been made. First by Bruce Love who made an 18
shifter (18 shifts to take out the first piece). Later Brian &
Susan Young brought out a 19 shifter and I helped them analysing
it. It is still not sure whether other solutions with the same
pieces and fewer shifts exist. And ultimately Go Pit Khiam of
Singapore made a 33 shifter. Again there has been a good
cooperation between Go Pit Khiam and me for analysing. The 33
shifter really has a unique solution, no skewing movements or
whackly intermediate states. I once asked Go Pit Khiam whether he
also designed this on the back of his forehead, but he answered
that it was purely a matter of careful computer analysis.
Another development of the 6x6x6 was made by Matti Linkola. With
again the same outward shape, he made one with no holes inside.
This means that the first pieces (or 2 pieces together) come out
directly. In France Pierlot has also made 3 no hole versions with
long bars. These ones are quite different and difficult and
cannot make use of the fact that pieces can pass over the end of
other orthogonal pieces.
I am very happy that so many other designers have been inspired
by my original 6x6x6 and I am proud to be able to present it for
the first time in a legal and correct version after so many
years. Of course there must exist several single copies, made
from the drawing in the book. Only Charles Gantt once made very
few copies with my permission (and with my name included!).
Unfortunately he died very shortly afterwards.
Willem van der Poel, 30th of January, 2004