Few days ago interesting puzzle idea came to my mind. I was reading about Johnson's Solids on Wikipedia when I found tridiminished icosahedron
. I haven't found here any puzzle based on this shape so I tried design it myself. However I'm not sure how should it be done correctly. Here's my attempt.
In above render each color represents different kind of piece. This puzzle has 4 planes of rotation (4 cuts):Face-turning cut...
...and 3 edge-turning cuts.
There's also possible jumbling-move on about 63 degrees (I haven't yet checked if it allows another moves on this mechanism, but I guess yes). The reason cut deepness is made way you see is I found it rather optimal both in appearance and mechanism. (of course I may be wrong
And mechanism now. Edge-turning moves are allowed by using spherical 'rails' (hope you know what I mean ;p).
As you can see bottom piece of the puzzle is its core. That cylindrical thing is the analog of standard 3x3 cube 3-d cross (place where screws are placed).
Puzzle has also 4 more screws, however they're not stationary but floating.
This should allow horizontal layer to move correctly.
Screws and circular 'rails' should keep upper blue and orange pieces in place.
Ok. This was my concept of mechanism, but there is one (at least) problem. On third and fourth pictures (edge-turn & jumble-turn) you can see that orange corners could easily fall off. Same thing happens if we turn edge-layer by 90 degree.
Three upper pieces aren't kept in place by anything. (similar pieces on left and right can be moved but won't fall off because of puzzle shape).
I found few solutions to this. First is to pillowing the puzzle. Second idea is to not making horizontal cut, but I'm afraid that puzzle would be to easy to solve due to only 3 cuts. Horizontal cut can be made also from the bottom, but it would make mechanism more complicated. I'm not pleased with those three, so I need your advice
What can be done here to improve the design?
Also, feel free to design your own version if you wish (I believe you can make it way better since I don't have much experience).