Taper Pins - Metric
Taper pins are small, solid steel tubes that resemble dowel pins but that are tapered – one end has a greater diameter than the other end.
They are manufactured to a very high tolerance to ensure that they are a precise fit. They are generally used for locking components in place in mechanical engineering applications, often in gearboxes and on camshafts.
Taper pins are tapped into position with a hammer or drift.
Metric is the most common thread type in production today. Usually specified as M then a number x another number. This signifies the thread diameter and the length of the fastener.
For example M4 x 30 means that the major thread diameter (the external distance across the outside of the thread) is 4mm and the length is 30mm. Length is usually measured from the underside of the fastener head.