Let's talk cue-ball physics. This episode: Stun and Screw

Stun and Screw

1/ Stun

A stun shot is mostly used to freeze the cue-ball after impact with the objectball. 

In this episode we will talk about stun and screw combined, because when the distance between the cue-ball and objectball gets higher then you will need to play lower on the cue-ball wich actually is a screw shot. It's very important to strike the cue-ball on the correct spot in relation to the distance between the cue-ball and objectball. A very important part combined with the distance between the cue-ball and objectball is cue acceleration and cue speed. Here, the same factors come into play, such as the state of the cloth, the state of the balls and much more, as already discussed in the previous episodes. The stun shot is mostly played without side, except when you want to straighten/change the line/trajectory of the cue-ball outcome.The closer the distance between the cue ball and the object ball, the more the cue ball can be hit higher on the vertical ax to stop forward motion of the cue-ball. The cue-ball after being struck is more or less gliding on its way to the objectball this depending on the distance of travel. By striking centerball with a certain amount of distance between the balls it is also possible to play a stun run-through where the cue-ball doesn't freeze but after contact keeps the desired forward motion.

2/ Screw

A screw shot is played low on the cue-ball to draw the cue-ball back from the objectball. The lower you strike the cue-ball the more backspin you will apply. To get maximum backspin you are going to have to hit the objectball full ball with the cue accelerating at maximum velocity the moment the tip strikes the cue-ball. When the objectball is not hit full in the face there will be loss of spin because it will arc and start sliding sideways resulting in loss of cue-ball motion. Also when the cue-ball hits the objectball at any angle there will be a front arc first before the cue-ball spins backwards. As already discussed in previous episodes the cloth is playing a very important role here. On a newer cloth it is a lot easier to play screw shots because there is less friction resulting in a sliding motion of the cue-ball going forward and losing less speed before hitting the objectball, resulting in more spin left on the cue-ball to start spinning backwards. 

No need to say because of a sliding cloth, clean balls and striking the cue-ball so low any side applied wanted/unwanted will push the cue-ball maximum off line resulting in spin loss and probably miss the pot altogether. A stiffer cue, a bigger tip, a softer tip, will result in even more problems throwing the cue-ball off line. A low deflection cue can significantly enhance your chances of potting balls with extreme spin or unwanted side. Remember this when trying to play a screw shot, it's not aiming low on the cue-ball that does the trick. It's hitting low on the cue-ball at tip impact. 

Next episode: The Chinese girl....Ei Ming

Let's strike the correct spot.