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Torque Wrench Use

This article will discuss the use of the TW-1 and TW-2 torque wrenches.

See also related topics Torque Specifications and Concepts and Basic Thread Concpets.

The TW-1 and TW-2 are very simple in their operation. Both tools are accurate and durable. The TW-1 1/4" drive and comes with an adaptor to accept 3/8" bits. The TW-2 accepts only 3/8" drive sockets.

On either tool, a steel beam deflects as the handle is pulled. The pointer beam remains un-deflected, and the beam below flexes and moves with the handle.

Hold only the knob of a beam type torque wrench

The reading is taken at the end of the pointer. The reading plate will have a series of numbers. Push the handle until the desired reading is attained.

Take the reading at the end of the pointer

The TW-2 has a "floating handle". Hold the handle so it "floats". You will see that by doing this, the load is placed exactly at the pin in the center of the handle. The distance from the pin to the head is a known distance. The more the metal deflects, the greater the load is applied at the socket. The smaller beam does not deflect, it is a reference for the larger beam.

Hold handle to neither end touches tool

To check tool calibration, have a look at the pointer when the tool is at rest. If it is pointing at 0, it is accurate. If it is off, bend the pointer shaft unit it points at 0. These wrenches are accurate both for both left and right hand torque, and there is no chance that the beam will fatigue and lead to inaccurate readings. Be sure to use a thread preparation, either grease, lube, or an appropriate grade of Loctite, on the threads.

Tighten crankbolts

Also see related technical articles at Bicycle Torque Specifications, and Basic Fastener Concepts.