How to Measure a Taper Pin

What are taper pins?

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

How do you measure a taper pin?

First, measure the overall length of the pin, then the diameter.
The key point to note with diameter is that metric and imperial taper pins are measured differently. For metric sizes you measure the smallest end to obtain the pin diameter. However just to make it confusing, for imperial sizes you measure the largest end!

Metric and imperial taper pins also taper slightly differently, with metric tapering at a rate of 1 in 50 and imperial at a rate of 1 in 48.

We have no doubt that there is a genuinely good reason for this but we’ll leave that one to the scientists and mathematicians!

How do you install a taper pin?

Taper pins are tapped into position with a hammer and drift.