Oversized Key Stock
Key stock is steel (usually carbon steel or stainless steel) in bar form that is used to make shaft keys (AKA machine keys) to lock shafts and mating components and to transmit torque from a shaft to component. The key stock is typically cut-to-size in the field to create machine keys used in repairs and rebuilds. Machine keys serve as a locking mechanism between the key way on the outside of a shaft and a mating key way pierced into the inside diameter of a pulley or gear. The fit provides the torque needed for a transmission turning the shaft, so it can also turn the gear or pulley. The key also serves as a safety stop. As its name implies, oversized key stock is larger than undersized key stock to help ensure a snug key fit. Items vary by dimensions, finish and material, among other considerations.