David Alciatore ("Dr. Dave") ILLUSTRATED PRINCIPLES "Squirt Part I: introduction" Summary: David Alciatore ("Dr. Dave") ILLUSTRATED PRINCIPLES "Squirt ­ Part I: introduction" Note: Supporting narrated video (NV) demonstrations, high-speed video (HSV) clips, and technical proofs (TP) can be accessed and viewed online at billiards.colostate.edu. The reference numbers used in the article help you locate the resources on the website. If you have a slow or inconvenient Internet connection, you might want to view the resources from a CD-ROM or DVD. See the website for details. This is the first article in a series dealing with "squirt." Squirt, also called deflection or cue ball deflection, refers to the angular change in the initial cue ball (CB) direction due to an off- center hit. Diagram 1 illustrates the effect. When the CB is hit off center, to impart English (sidespin), in addition to the large force in the aiming line direction, there is also a small sideways force that pushes the CB off line. In other words, the CB does not go where you are aiming. The squirt angle is a measure of how much the deflected cue-ball path differs from the aiming-line direction. I prefer the term "squirt" to "deflection," because when talking about a "low-deflection" shaft, things can be confusing. A "low squirt" shaft produces less "CB deflection" than an average shaft; but the end of the cue stick, because it is lighter than normal cues, actually deflects more after impact with the CB (e.g., see HSV A.109). So a low-squirt shaft produces smaller CB deflection, but it results in larger cue stick deflection. That's why I think the term "deflection" can be confusing when discussing cue sticks. large cue force Collections: Engineering