If weight needs to be removed to bring the crankshaft into equilibrium then a drill press, that is attached to the balancer, is used to remove material from the weights. The depth and size of the hole is determined by a drill chart that identifies the weight of material displaced by drilling. If mass is to be added to the crankshaft to compensate for heavier reciprocating components or increased stroke, then a hole is drilled axially to accept a heavy metal slug made of tungsten. It is customary to press-fit and then weld the slug in place. Heavy metal installation usually shows a 2:1 ratio. If one gram of steel is removed, the area displaced will hold 2.17 grams of tungsten.