WHAT IS MEANT BY PIN PLACEMENTThe pin is a colored dot on the ball that signifies the position of the top of the core in the ball. With today's high-tech bowling balls, the ball driller must know where the core is in the ball. When a ball is built, the core--anchored by a small rod--is suspended in a mold, and the cover stock is poured into the mold. When the cover material hardens and the ball is removed from the mold, the rod that was holding the core of the ball in the mold is removed. Now there is a hole in the ball that has to be filled, and it is filled with plug material, which on the surface on the ball looks like a dot.
As the cores of the modern-day resin urethane balls became so strong, and as our understanding of the core's influence on the motion of the ball advanced, it became important for the ball manufacturers to color the plug so we could see what we were dealing with. Today there is no high-performance ball that doesn't identify where the core is and how far it is from the center of gravity, or "cg." The cg is marked by a small punch mark on the surface of the ball. The position of the cg relative to the pin determines how we drill the ball for the reaction we're trying to get. — Talk with your ball driller if you don't know what pin position would be best for you. |