Ranzha's Skewb Method — For Beginners
Hello! If you're a beginner to Skewb solving, here's the place to be! I recommend that you know how the Skewb turns as well as notation. You don't need to know how to solve a Skewb before looking at this tutorial, but I'd recommend having a working understanding of how the puzzle operates before looking into this method. The goal of this tutorial is to by the end have a solved Skewb.Jump to: Step One | Step Two | Step Three | Step Four
Step One: The Petrus Block
As outlined on the homepage, there are four steps to this method. The first is called the Petrus Block.
This step can be solved optimally in no more than five twists and is completely intuitive. However, as this is a tutorial for beginners, a beginner's intuition may not serve to keenly as to the formation of the Petrus Block.
For this reason, below are some substeps (with inspiration from acubist) that should aid in Petrus Block building.
Substep 1a: 1 Centre + 1 Corner
Substep 1b: Forming the Rest of the Block
Since we're going to be attaching two pieces to our current block from substep 1a, it should be noted that there are three ways of doing this, two of which are beginner-friendly. Here they are:
Substep 1b1 | Substep 1b2 | ||
Substep 1b1 attaches a centre onto the 1a block before inserting the final corner piece for the Petrus Block. | Substep 1b2 does the opposite, attaching a corner piece before the corresponding centre piece. |
Substep 1b1: Attaching a Centre, then a Corner
Attaching the following corner piece isn't nearly as easy. Using the olfactory piece insertion technique (open slot, position piece, close slot), we can insert the final corner of our Petrus Block. First, try positioning the corner in the position as indicated at left.
Positioning this corner here is the perfect setup for our open, position, and close technique. By doing R F R', the corner becomes attached to the block, completing it.
However, this corner, although permuted, may be incorrectly oriented in either of two ways. Alternatively, it could be solved. Here is a table of all the possibilities for this corner's orientation, along with intuitive algorithms to fix each unsolved case.
Solved | Clockwise | Anticlockwise |
Step is solved! |
R F' R' L R F R' |
R F' R' L' R F R' |
Basically, take the corner out, twist it correctly, and put it back in.
Now, the Petrus Block should be solved! Here's the other way of solving the last two pieces of the Petrus Block. If you don't care to read, click here to jump to Step Two: The Welder's Mask.
Substep 1b2: Attaching a Corner, then a Centre
Attaching a corner to the 1a block is very easy and takes at most three twists. Experiment! Make sure that the 1a block never disconnects.Attaching the following centre piece can be difficult at first, but the task becomes easy once you get the hang of it. Luckily, the final centre of the Petrus Block can be solved in at most four twists.
However, as optimality isn't our ultimate goal in this tutorial, to make this process both easy and efficient, here is a more streamlined approach.
Then, holding the Skewb as the image shows, use the algorithm F' R F R'. This algorithm and its inverse are arguably the most important of all Skewb algorithms. You'll be using this algorithm a lot.
Now, the Petrus Block should be solved!
Step Two: The Welder's Mask
In this step, you'll attach the remaining two corners with white in them in their respective positions on the top. This corner positioning forms the Welder's Mask.
There are three particularly cool things about this step:
Skewb Cool Things:
This step only uses F and R turns. Neither of these turns disrupts the Petrus Block in the top left.
These corners are not interchangeable--that is, the UFR corner cannot move to the UBR position via turning.
The bottom layer corners will permute. This is due to the nature of the puzzle.
As an added bonus, each Welder's Mask case can be optimally solved using F and R turns in six twists or less.
To go about solving the Welder's Mask, we must first position the corners in the correct locations, and then orient them with the use of four short algorithms.
Substep 2a: Permuting the U Corners
This substep can be completed intuitively in two twists or less every time. Here's why:
The corner that belongs in UFR can be in either of three positions (UFR, DFL, DBR). This set of corners can be cycled independently through the use of F twists.
The corner that belongs in UBR can also be in either of three positions (UBR, DFR, DBL). This set of corners can be cycled independently through the use of R twists.
These sets of corners ,coupled with their counterparts in the Petrus Block, cannot be permuted in themselves, in the same way that the centre pieces on a 3x3 cube cannot change position relative to the other centres.
Because cycling one set of the corners doesn't affect the permutation of the other set, cycling each set so that each remaining U-layer corner is correctly permuted will take at most two moves (at most one for the first corner (F or F' or nothing), at most one for the second corner (R or R' or nothing).
You should be able to figure out which moves to make to permute these corners. Just make sure that the Petrus Block is NEVER broken during this step.
However, if you want straight-up move sequences, here are some:
If a white corner is in DFL, to move it to the UFR position, do an F move.
If a white corner is in DBR, to move it to the UFR position, do an F' move.
If a white corner is in DFR, to move it to the UBR position, do an R move.
If a white corner is in DBL, to move it to the UBR position, do an R' move.
Substep 2b: Orienting the U Corners
Orienting the U-layer corners once they're permuted can be performed intuitively just as the initial permutation step. But for the algorithmic learner, through the use of four four-move algorithms (two of which orient the corner in the UFR slot, the remaining two of which orient the corner in the UBR slot), this substep can be performed in eight twists or less. Here are the algorithms now:
UFR Anticlockwise | UFR Clockwise | UBR Anticlockwise | UBR Clockwise |
(R F R' F') |
(F R F' R') |
(R' F' R F) |
(F' R' F R) |
Step Three: Last Four Centres
In this step, you'll solve the remaining centres of the puzzle. This step breaks the intuitively intended system of the steps prior by introducing proper algorithms!
(hover for hidden faces)
If your Skewb has 0 unsolved centres (that is, all of your Skewb's centres are solved) proceed to Step Four by clicking here.
There are a total of six cases for this step:
Three cases involve solving a cycle of three centres, and the other three cases solve four centres.
Important: Use y rotations so that your Skewb's centres are being solved as the pictures denote.
(hover for hidden faces)
U R-L-D |
Oa R-D-F |
Ob R-F-D |
(F' R F R') y2 (F' R F R') |
y2(') (R F R' F') y' (F' R' F R) |
y (F' R' F R) y (R F R' F') |
(hover for hidden faces)
H F-B, R-D |
Za F-R, B-D |
Zb F-D, R-B |
(F' R F R') |
(R F R' F')*3 |
(F' R' F R)*3 |
Step Four: Corners of the Last Layer
At this stage, the only pieces left to solve are the corners of the last layer.
To solve the corners of the last layer, we will use the classic 4-mover F' R F R' various numbers of times.
Peanut | (F' R F R')*2 y (F' R F R')*2 |
Pi | (F' R F R')*2 |