Beam-Type Torque Wrench Use and Calibration
This article will discuss the use and calibration of beam-style torque wrenches such as the TW-1.2 and TW-2.2, as well as the TW-1 and TW-2 (discontinued).
Use of Beam Wrenches
Park Tool beam-type torque wrenches are are accurate, durable, and very simple in their operation. The TW-1 features a 1/4″ drive and comes with an adapter to accept 3/8″ bits. The TW-1.2, TW-2, and TW-2.2 accept only 3/8″ drive sockets.
On beam-type torque wrenches, 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.
The reading is taken at the end of the pointer. The reading plate will have a series of numbers in both Newton meters (Nm) and inch-pounds. Pull the handle until the desired reading is attained.
To check tool calibration, inspect the pointer when the tool is at rest. If it is pointing at 0, the tool is calibrated. If it is off zero, bend the pointer shaft unit it points at 0. Place a screwdriver or similar lever between the two beams closer to the head than the scale. Bend the small shaft until the point is at zero when the tool is at rest.