I have opened my 2x2x3 too many times, and the glue seal that holds the hidden layer from shifting broke. What pieces must i glue? i didnt make this in the first place, so i dont know.

There should be 4 glued together in total:

- the center of either the top or bottom 2x2 face
- any adjacent corner to that center
- the two edge cubies that share sides with both the center and corner you chose

It's unlikely that the bonding between all four of these broke at the same time, I should think. Make sure that none are glued together already before glueing new ones. Also, can't you tell which were glued before from glue residue?

Sandy

- the two edge cubies that share sides with both the center and corner you chose
inner corners?

A = a center cubie on one of the two faces of the kernal that becomes a 2x2 face when the attachments are in place
B = any one of the four corners on that same face
C & D = the only two edge cubies that share sides with both the center and corner you chose

-------------
|   |   |   |
-------------
|   | A | D |
-------------
|   | C | B |
-------------

(For a better graphic, see the Fisher article, Figure 5. Glue where the dotted lines are on the kernel.)

Essentially, one of the corners of one of the 3x3x3 kernel gets extended into a 2x2x1 cubie. That "cubie" then moves around the 2x2x3 as a single unit, forcing the rest of the kernel cubies to remain lined up under the attachments.

Come to think of it, that would make an easy way to play with a 2x2x3 without building one. Remove the center column of stickers from the four edge faces, and all but the corners on the top and bottom faces, then bond four of the top (or bottom) face cubies into a 2x2x1. The resulting puzzle will act like a 2x2x3.

Sandy

Thanks sandy, it works great now.
Btw: they didnt all break off. the corner, and one edge came off. No residue. Ill keep in mind that it is glued, next time i want to open it. I thought it was just being Fussy...