Rules of the torque wrench, explained

I would bet that you and most other Shop Press readers have a pretty good handle on how to use a torque wrench. You aren’t going to get far in this industry without a proficient understanding of how to employ and care for these precision instruments.

And if you’re anything like me, you had to make a few mistakes and maybe even try some experiments of your own to get through the early learning curve. I clearly remember a few lessons learned on a torque wrench borrowed from my dad when I was wrenching on projects back in high school. (Sorry, Pops.)

Whether you have a brand-new digital unit, a cheap clicker, or a trusty old beam wrench, no torque wrench is able to do its job properly unless you know (and follow!) some of the immutable laws of torque application, such as:

• Thou shalt not store thy clicker wrench without resetting its adjustment knob
• Thou shalt not use a flex adapter with thy torque wrench
• Thou shalt not lubricate threads on a fastener before tightening with thy torque wrench unless specifically instructed
• Thou shalt not drop or abuse thy torque wrench, lest it no longer tell the truth

I find it easier to follow a rule if I understand why it exists in the first place. For those of you still learning the ropes, I think this video from Torque Test Channel on YouTube does a solid job of demonstrating “the why behind the how” of torque wrench use. And for the more experienced techs out there, there are some good refreshers and examples in the video to affirm the habits you’ve built over the years. (And let’s be real here, there are some tests you’d never try with your nice personal wrenches no matter how curious you might be.)

That original video prompted a lot of comments and questions, and if you want to continue exploring some of the finer points of torque wrench use, check out the follow-up video here.