In the first rack in straight pool ( when you place all the balls together before the break ) , the fifteen object balls ( the colored balls ) are racked in a triangular frame , usually made from aluminum , wooden , or plastic . The center of the ball at the top of the rack is placed over the a spot on the table called the foot spot . In the initial in straight pool , the fifteen are racked in a triangular rack , with the center of the apex ball placed over the .