Solving Rubik's Cube for speed.

By Lars Petrus

Introduction

This is a tutorial for my method of solving Rubik's Cube. It is intended both for beginners and experienced cubers. There is no group theory or written notation involved, I just show you how to move. You very much need a Java-enabled browser.

Using this method, I won the 1981 Swedish championships, and finished 4th in the 1982 world championships in Budapest. I also won the 2005 world championships in Orlando for solving in fewest moves. My average of 10 best is 21.88 seconds from 2002, and for a single solution 13.60 in 2006.

I'm very happy to provide this
site as a free service to the world!
If you want to send money, I'm
also very happy to receive it :)

Please take a look at my terminology, so you know the difference between a turn and a twist, for example.

If you are a total beginner, look at this description of the basic concepts of Rubiks Cube.

The animated Java cubes that are used for illustrations and examples are explained here.

The Basic Idea

Most people solve the cube layer by layer. This is a simple way for the human mind to approach the problem, but it is useless for speed cubing. No matter how good you are, you will use more than 100 moves. Going for speed, I use 60 moves on average. Going for few moves, I average 45.

In the final of the Swedish championship, 8 of 11 competitors used a vanilla layer-by-layer method. The other 3 of us finished 1, 2 and 3!

The basic problem with the layer method is a big one, and it's obvious once you realize it. When you have completed the first layer, you can do nothing without breaking it up. So you break it, do something useful, then restore it. Break it, do something, restore it. Again and again. In a good solution you do something useful all the time. The first layer is in the way of the solution, not a part of it!

The Method

The Petrus method has 7 steps:

• Step 1 - Build a 2x2x2 corner
• Step 2 - Expand to 2x2x3
• Step 3 - Twist the edges --- 2, 4 or 6 bad edges
• Step 4 - Finish 2 layers --- Step 4b tricks
• Step 5 - Position the corners --- Complete Step 5+6 index
• Step 6 - Twist the corners --- Complete Step 6+7 index
• Step 7 - Position the edges
• Step 1, 2 & 4 - Block building tricks
• Practice - 13 example solutions

I also have some tips on the physical as well as the mental aspects of speed cubing.

You can download the java code for the cubes.

Fun and Games

And a java cube you can solve on time.

Thanks and Credits.