Two elements of pool are needed to run out a rack during every game: pocketing and position. The easier the shots you leave yourself during a rack, the better chance you have of running out and beating your opponent. One of the simplest methods to get good position is to use the clock system which was designed by Buddy Hall, one of the best position pool players of all time.
The system is used to measure how much spin to use on each shot to get precise position from ball to ball. And the way to measure the spin is to view the face of the cue ball like the face of a clock. So straight top spin is 12:00 on the cue ball whereas draw is 6:00. Along with that, at 3:00 the hour hand is on the right, so on the cue ball that represents right english with no top or bottom. And finally, 9:00 represent left english.
Here’s a brief video from Buddy Hall himself explaining how the system works.
The reason this system is great is because each number on a clock represents a diamond on the pool table. It’s incredibly easy to get position from ball to ball using this system because it helps take the guess work out of where the cue ball is going.
The key is finding out how your stroke works with this system. Even though 1:00 will get one person to the first diamond past the side pocket for some people, you may need to hit the cue ball at 2:00 to get the result you want.
It’s also worth nothing that this system needs a consistent stroke to work well. If you’re not accelerating through the cue ball the same way for every shot, then you’re going to get inconsistent results. And if you do try this system you may notice that the speed you hit the ball influences how this system works. This is true, since the cue ball might be coming off at a different angle on the rail if you’re using bottom spin or top spin which will affect how the english carries off the rail.
However, despite some of the challenges that come with the clock system, the rewards far outweigh this systems difficulties. You’ll be able to accurately and consistently aim for diamonds around the table which will make your job of moving that cue ball so much easier when you play pool.
P.S. I know the video above is a little grainy, but it’s nice to hear about the clock system from the man himself. Having said that, here’s a much more recent, clearer video made by famous cue maker Bob Meucci.