While this might be a little underwhelming after the Multidodecahedron, this is still a very interesting puzzle. A 3x3x3 that can only do 180 degree turns on all faces has already been made by Hidetoshi Takeji
and a variant is for sale in Oskar's Shop
. A variant where only one axis allows 90 degree turns has also been made.
However, the remaining variant where only one axis is constrained to 180 degree turns has not been made yet. It was of course Andreas Nortmann's request to make one.VIDEO
This puzzle represents a unique challenge in it's design: the half turn only cube can be made by bandaging a 7x7x7 and the one which is constrained on two axes can be made from a 5x5x5. This can also be seen as using different proportions for the cuts of each axis. However, the variant where only one axis is limited can not be made this way because the moment you make just the cuts of one axis disproportional two axes are instantly limited.
My solution is to work from the centerpieces, adding internal parts that block illegal turns. This mechanism could be used to construct many other puzzles, like a Helicopter Cube that does not jumble. If Adam Cowan were dead, he would turn in his grave so I will not be doing that.
Unfortunately, the blocking mechanism is hidden from view and there is nothing external about the puzzle that hints as to what it does or what the internal state is. I have made some very neat printed stickers to indicate which faces are limited but they still don't tell you if you're in a legal state or not.
This puzzle is for sale in my shop, starting at just $90/€75. This includes a free set of printed stickers, shipped from me to you (does not come with your Shapeways order). Additionally, you can buy assembled and stickered copies directly from me. Click here to buy your 3x3x3 limited to 180 degrees on one axis cube in my shop
. Oh, and sorry about the terrible name.VIDEO