U turn sans U turns

All elements of the Rubik's cube group may be generated using turns of only five of the six faces, say all but the Up face. This suggests a puzzle variant: a cube with the Up center cubie glued fast. Has any work been done on such a puzzle? I played with this a bit today. Here's an U turn macro using no U turns:

B D' F L' F' B D F' R B' L F' D F B' L' F

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There are shorter maneuvers f

There are shorter maneuvers for this (in the face-turn-metric):

L R B2 F2 L' R' D L R B2 F2 L' R' (13f*)
L R' B2 F2 L R' D L R' B2 F2 L R' (13f*)

You can generate them directly with Cube Explorer with a little trick.

1. Gray out e.g. the UF-edge cubie of a clean cube by right clicking in the Facelet Editor.
2. Make an F(!)-turn with the "Apply Move" button.
3. Press "Add and Solve".
4. A maneuver window appears which generates solutions.
5. Stop the search.
7. Check the F-box in "Faces to exclude".
8. Press "Add and Solve" again. Now only solutions which generate the F-turn without using the F-face are generated.
9. "Add solutions to Main Window".
10. To get the solutions for U-Turns Right click on each cube and "Rotate 1/3 about URF corner".
11. File|Save Maneuvers.
12. The textfile contains the generators for the U-Turn.

In a similar way I got for example the "Cube in the Cube" pattern without an U-turn in 16 moves

R' D' L D F' R2 D' F D2 R B2 R' D L' D2 R (16f*)

For random cubes this method might be too slow, because the module for solving incomplete cubes has only small pruning tables.

re Five Face Puzzle

Seventeen is the optimum in the q-turn metric. When I started to consider this I put together a macro composed from several edge+corner double swaps and it took me 87 q-turns.

I have since disabled one face turn and solved several random cubes manually. It turns out not to pose that great a handicap, a least not with my method. I average 85 to 90 q-turns normally and disabling one turn adds maybe 10 to 15 turns extra.

I remember reading an old book

I remember reading an old book (probably in 1983) on the Cube that displayed this trick, and the maneuver had the name of its discoverer, but I don't remember what it was.
The solution was the second one submitted by Kociemba.