Fundamentals
The common language of every system: table coordinates, diamonds, numbering, diamond theory, the spin scale, ball fraction and speed.
The table and the diamonds
On this site the table is always drawn vertically. It is 4 diamonds wide and 8 diamonds long; the unit is the distance between two diamonds.
There are 3 diamonds on each short cushion and 7 on each long cushion. The diamonds sit outside the cushion nose, on the diamond line; system values are read on this line.
Move your finger or mouse over the table to see the coordinates of any point.
How to read the numbering
Each system puts its own numbers on the cushions: the start, aim and arrival scales. The same diamond can carry different values in different systems.
Numbers in the outer row are read on the diamond line; numbers in the inner row are read just inside the cushion nose. Values in between are found by linear interpolation between two marks.
The colors are the same everywhere on the site: start is turquoise, aim is orange, arrival is purple.
Diamond theory
The basic relationship: Start − Aim = Arrival. Know any two and you can find the third; most often the value you need is the aim: Aim = Start − Arrival.
Example (40 in One, opening shot): on a table that plays normally, the arrival at the 3rd cushion is about 27.5. With a start of 29.5 (≈30), the aim is 29.5 − 27.5 = 2.
The cue ball must lie on the reference line that joins the start point and the aim point.
The spin scale
Spin is measured from 0 to 4. On high hits (0a, 1a, 2a, 3a) the contact point is in the upper half of the ball, about 0.8 of a radius from the center, and moves sideways in steps of 22.5°; 4 is full side on the equator.
On middle hits (0m, 1m, 2m, 3m) the contact point moves sideways from the center along the equator. 0m and 0a are the same, and 3m corresponds to roughly 2a.
Negative values are reverse spin: the contact point is on the other side, on the same scale.
Ball fraction
Ball fraction describes how much of ball 2 the cue ball covers. On a 1/2 ball hit, the center of the cue ball aims at the edge of ball 2.
The fuller the hit (3/4, full ball), the more speed ball 2 takes and the less the cue ball opens up; the thinner the hit (1/4), the more speed the cue ball keeps.
In pase bola systems you take the ball thin as a rule; in System 30, on the other hand, you take a lot of ball.
Speed
Systems hold within a certain speed range. In the Renversé, speed has a very large effect; System 30 calls for a firm stroke; no-spin rodadas are played with enough speed to complete 3–4 cushions.
Repeat each system's reference position until your spin and speed are consistent. Values drift as the table and the cloth change; that is why the personal table value (Tüzül) exists.
Applying a system
1. Identify the position: the cushion order and the type of shot (ball first, bricole, pase bola, renversé).
2. Read the start and arrival values from the system's scale.
3. Apply the formula, then add the system's corrections in order.
4. Mark the aim point on the diamond line, check the reference line, and play with the spin and speed the system calls for.