Zen and the Art of reverse automotive engineering

Torque Wrench

August 19th, 2008 the Mad Scientist

The torque wrench is one of the most universally useful hand tools available to the home mechanic.  These magical little tools take the guesswork out of the amount of twist you’re putting on bolts, greatly reducing the risk of shearing the heads off of them.  You can also rest assured that high-torque bolts and lugs are more likely to be close to specifications.  Without a torque wrench, 40ft/lbs feels very similar to 80ft/lbs, but can be the difference between a wheel falling off while you’re on the freeway and having an uneventful cruise.

Mechanical torque wrenches come in two flavors:

Beam Style torque wrenches use a beam of spring steel that is bent by the force you put on it.  These are accurate enough for most backyard repair and part replacement jobs, and are inexpensive enough that it won’t break your budget.  For a first torque wrench, I highly suggest a Beam-StyleTorque Wrench.

Click Style (pictured) torque wrenches use a clutch-style mechanism.  These are generally more accurate than beam torque wrenches, but are more expensive because of their complexity.  The SK Micrometer Torque Wrench is one of the best feeling torque wrenches I’ve had the privilege of handling.

Photo courtesy of exfordy.