Spin and the Tangent Line

Written by David Baranski

Page 2 of 4:  First ·  Prev ·  1 ·  2 ·  3 ·  4 ·  Next ·  Last


Diagram 3
Article Index
The Tangent Line (page 1)
Cue Ball Path (page 2)
Cue Ball Path - Continued (page 3)
Determining Correct Spin (page 4)

Line C is the path of the CB when using follow. Line D is the path of the CB when using draw. Notice that the CB follows the tangent line before rolling forward or coming back. This path is actually a parabola. Once the CB contacts the OB, it follows the tangent line until friction grabs the ball and the spin causes it to move forward (follow) or backward (draw). If the CB is struck harder, it stays on the tangent line longer. If we use follow and strike the CB hard, it would follow this line (see Diagram 3).

Line C is the path of the CB when using follow with a medium stroke. Line D is the path of the CB when using follow with a hard stroke. Notice that the CB path stays on the tangent line longer before moving forward to the short rail. The same parabolic path applies to draw, just on the opposite side of the tangent line.

Follow and draw alter the path of the CB after contact with the OB. English, on the other hand, alters the path of the CB after it contacts a RAIL. English has no effect whatsoever on the path of the CB if the CB doesn't touch a rail. Some players will swear that this last statement is false. I assure you, my statement is true. There are two shots that prove this. 1) Set up a short straight in shot. Use left english with no draw or follow (dead 9 o'clock). Stroke firmly with a level cue. Pocket the OB. The CB should just spin in place. 2) Set up the cut shot in the diagrams above. Use left english with no draw or follow (dead 9 o'clock). Stroke firmly with a level cue. Pocket the OB. The CB will follow the tangent line, it will not roll forward or backward of the tangent line. The CB will react differently once it contacts the rail, however.


Diagram 4

There are two types of english: running and reverse. Running english "opens" up the rebound angle off the cushion and helps the CB “run” around the table. "Opening the angle" means that the angle created when using running english is larger than it would be if no english were used (see Diagram 4).

Page 2 of 4:  First ·  Prev ·  1 ·  2 ·  3 ·  4 ·  Next ·  Last

About The Author: David Baranski is an instructor and pool player from Raleigh, North Carolina.

Related Articles

Author Info - David Baranski