Void Cube Tutorial

Behold, the 3x3x3 Void Cube (at front and center).

Among myriad variants on the original Rubik's Cube (a step behind it, at our left), it comes perhaps closest to being exactly like the original puzzle. The one obvious difference is that instead of a center piece on all six sides, there's a hole which (take my word for it) you can see right through to the other side. If you have a finger long enough and slender enough, you can poke it right through, too – though I think the initial form of this concept was simply a Rubik's Cube that omitted the colored stickers on the center pieces, leaving blank centers that had no bearing on the puzzle's solution. Otherwise, solving it is exactly like solving the Rubik's Cube.

Joining Rubik in the cheering section (back row, above) are three other seemingly minor glosses on the classic 3-cube. At left is the Twist cube, which appears to have been twisted so that the edges now run through the centers on all four middle layers, while the centers have become (as it were) edge pieces. As we'll see in an upcoming tutorial, solving the Twist Cube is almost exactly like solving the O.G. Rubik's Cube, only with about 20 percent more swearing. At back row center and right are some cuboids: the 3x3x4 and 3x3x2, to be precise. Solving them isn't like doing a 3x3x3 at all. But that's a story for another time. There are more like them, but this is as far as I've branched out into cuboid territory – unless you count the 2x2x4 Rubik's Tower, which I think of as more of a gloss on the 2x2x2 Mini Cube. So, we'll meet that oddity at a later date.

The reason I bring these particular modifications of the Rubik's Cube together is to introduce a new chapter in my series of cube tutorials: To modify a phrase coined by Douglas Adams, these are all puzzles "almost but not quite entirely like Rubik's Cube." In the case of the Void Cube, it takes away one thing but gives another. On one hand, you can't use the centers to, as the beginner's method for the 3-Cube puts it, "find the center" of the adjacent piece edge or corner piece. To figure out where those pieces go, you either have to look for other cues (like the edge pieces that form the White Cross) or, in assembling the White Cross, remember what order to put them in around their shared void. Keep repeating to yourself, "B-O-G-R" – blue, orange, green and red, going counterclockwise around the side that (gulp) doesn't have a white center. On the other hand, you don't need to find those centers; you could arbitrarily pick a center, call it white, and start building the White Cross around it, and everything follows accordingly.

Since the 3-cube's centers are fixed in relation to each other, you may even come to realize that the centers are trivial. But then you'll try an experiment like trying to solve the Rubik's Cube with all of the centers out of alignment and the resulting disaster will leave you humbled by the inscrutable math of the Rubik's Cube. But I get ahead of myself. Let's get back to the Void Cube, and a probably unnecessary tutorial that really adds nothing to the beginner method for the 3-cube, except that it manages not to make reference to the centers.

Here's a 3x3 scramble pattern, from a page I keep bookmarked on my phone. If you haven't done likewise by now, get with it.

And here's that scramble, executed on the Void Cube. Obviously, to check whether I scrambled it correctly, you have to ignore the centers.

STEP 1: BOTTOM LAYER EDGES, a.k.a. the White Cross. Here I've put the white-green edge in position to dial in next to the white-red edge.

Next, I dial the orange-white edge up next to white-green.

And finally, here's blue-white going in next to red-white.

STEP 2: BOTTOM LAYER CORNERS. Put, for example, this white, blue and (trust me) orange corner above where it belongs and do an L'-U-L move to slot it in.

Then, do the same thing with the white-blue-red corner:

Here I've done something similar to get the red-green-white corner in place.

For the orange-white-green corner, we have to do a preparatory move to put the white piece at the side. Starting with the problem corner above an unsolved corner on the lower layer, just do an R-U2-R' move, then put put the white corner back above where it belongs and slot it in with an R-U-R' move.

You know how it goes. If one of the white corner pieces is already on the bottom, but in the wrong position, use either L'-U'-L or R-U-R' to put it back on top, than slot it into its proper corner down below. You know, like you've been doing since you started messing with the Rubik's Cube.

STEP 3: MIDDLE LAYER EDGES. Let's start with this orange-blue edge on top. Putting the front-side color above its matching bottom edge (duh, blue), dial it away from the side whose bottom edge matches its top color (so, orange). Then do L'-U'-L, give the cube a y' turn (to put orange at front), and do U-R-U-R' to put the side edge where it belongs. See? We don't need to slap the orange side of the cube. We don't need no stinking center. How we've grown!

This procedure is transferable (give or take a switch to a mirror-image move that starts on the right) to the red-green and the red-blue edges:

The orange-green edge presents the only possible complication: when a side edge piece is already in a side edge position, but placed incorrectly. Well, this case simply calls for an R-U-R' move, a y turn and (with orange at front) U'-L'-U'-L, to put the orange-green edge on top...

And then the starting-on-the-right version of the middle layer edge algorithm, R-U-R'-y-L'-U'-L. Result:

STEP 4: ORIENT LAST LAYER EDGES – a.k.a. the Yellow Cross. You know the drill by now: Putting solved yellow edges in the "9:00 clock hands" position, if possible – and to be quite frank, I've moved on toward looking for unsolved edges at 3 and 6 – do the algorithm that I still, to this day, whisper to myself every time I do it: F-U-R-U'-R'-F'.

If you're not lucky enough to have unsolved edges at 3 and 6, putting them at 12 and 6 is a good start; the algorithm above will give you the "9:00 clock hands" you need to complete this step.

STEP 5: ORIENT LAST LAYER CORNERS Given the void at the center, I suppose you could call this the Yellow Square. First, turn the yellow cross to put an unsolved yellow corner at front left. Then do that old chestnut, R-U-R'-U-R-U2-R'.

Repeat (always with a yellow "headlight" at front left) until you reach a state where there are exactly three unsolved corners.

Then put the one solved corner at front left and repeat the algorithm, and repeat again as necessary, until all four top corners are yellow-side up.

STEP 6: PERMUTE LAST LAYER CORNERS. Check for "headlights" (matching corner colors) on any side of the top layer. In the example below, the solid green bar will do nicely. Let the green corners find their, ahem, side (I almost said "center"), then put that side at the back and do the R' F R' B2 R F' R' B2 R2 U' pattern – which, strangely, I don't have to whisper to myself to ensure that I get it straight.

No headlights? No worries! Just do the algorithm regardless of which side is at back, then repeat this step from the top.

STEP 7: PERMUTE LAST LAYER EDGES. On a 3-cube, void or otherwise (and that goes for the Twist Cube as well), you'll either have zero, three or four unsolved top-layer edges at this point. If zero, congratulations; you solved the puzzle in six (or, sometimes, fewer) steps. If four, do the algorithm below, then repeat with three unsolved edges. If three edges are unsolved, as in today's example solve, put the solved side at back (in this case green), then do this move: F2 U R' L F2 R L' U F2. This should cycle the three top edges at right, front and left one step to the counterclockwise. You might have to repeat this step (or, if you're really brainy, learn the mirror-image move for a clockwise cycle) to finish the solve.

Full disclosure: The first time I did Step 7 during my example solve, I messed up and put the wrong side at back, which simply led to me having to repeat the move. Purely a matter of being in a rush to shoot the pictures; not at all a lapse of cubing skills. (Wink.) I omitted those 2-3 photos from this post to keep the focus on how-to, but I wanted to come clean in case there's an eagle-eyed expert out there who detects a gap in my photo editing.

This is where I wrap up with a review of the toy. I don't usually give a shout-out to a particular product, but in this case I really want to note that my personal Void Cube is described at SpeedCubeShop as "QiYi Racing Void Cube (Magnetic) - Stickerless." And I'd really like to urge anyone who's interested in leveling, erm, sidewise from a 3-cube to a 3-cube with Swiss cheese holes to adopt the same exact product. It's absolutely fabulous. In fact, I've decided it's my favorite 3-cube, notwithstanding the gaping void at its heart, based entirely on how it turns. My two vanilla 3-cubes include the one pictured throughout this post, which is actually stickerless though it doesn't look it, but has a pretty tight action; and then an honest-to-goodness speed cube that turns so loosely that it drives me nuts. This Void Cube falls into the Goldilocks Zone between the two, turning with the "just right" degree of freedom and smoothness. Plus, thanks to the tiny magnets inside, the layers snap into place as you turn them, which really cuts down on those awkward moments where multiple layers lock up together. It feels very satisfying to hold and it moves so sweetly that I just lurve it. Also, it presents an opportunity to freak people out by looking at them through it. Win-win-win.

Fans of the beginner method for Rubik's Cube may also have spotted the fact that this seven-step solution method is one step short of the 3-Cube's beginner method. The missing step is the "Daisy" (arranging the white edges around the yellow center), which is obviously not applicable to the Void Cube since there isn't a yellow center. You just have to assemble your white cross any way that you can, with their side-facing colors in the correct order. For discussion: Does that make this puzzle easier or harder than the vanilla 3-Cube?

Until next time, here's some homework for you. Take a close look at this Twist Cube and try to guess a couple of ways it presents a (ahem) twist on the 3-cube solution that might lead to elevated cortisol levels in your blood. Leave a comment if you like. Nobody does that anymore (except spammers; they're excused from the assignment).