Broken / Stripped Lugs When Using a Torque Wrench (a cheap one)

[marmathsen]

I'm curious how often others find that lugs break or strip out when using a torque wrench prior to reaching the rated torque value. I of course double and triple checked the setting on my wrench. The wrench isn't more than a year old, but I'll admit it is an inexpensive one from Home Depot 🫢.

I've had this happen a couple times recently and if I'm in the middle of a service change (Residential) it's a real pain in the butt. The last ones took two weeks to bring in.

On a related note, when I recently used this torque wrench I needed to torque to 275 in lb (~23 ft lbs) So I started at 20 ft lbs (Click!), then moved to 21 ft lbs but it Clicked without moving the bolt, moved up to 22 and again clicked without movement, and same with 23 ft lbs, no movement. So maybe it's my wrench? I've never torqued lugs this way before, I always just set the wrench and tighten 'til it clicks.

So maybe my questions should be:

How often to you see lugs fail below their rated torque values?

How often do you see torque wrenches get out of calibration?

Do you find that inexpensive torque wrenches just aren't worth it? I used to have a Wera but after it was stolen out of my van I bought a...Husky

 

[ptonsparky]

The old non digital were accurate enough and calibration was easy. Bend the pointer back to zero while it was at rest.

The last year or so I was in business I noticed neutral bar setscrews were inconsistent and would need to move the connection to a new location. It was obvious the wire was still loose at torque value.

I did occasionally have lugs in the same panel where the setscrew did not reach the same depth as the others. I will admit to stopping at some point where it was obvious the SS was not moving and something was going to break before it did.

I sent a Klein inch/lb screw driver in to be calibrated once. Almost as expensive as getting a new one.
A nephew works at a nuclear plant in the SE part of the state. They check calibration each time a tool is checked out.

I would not expect to start the movement of lugs in 1 lb increments. The bending bar wrenches would show about where it would start to move again.

 

[hillbilly1]

When I was in automotive shop class in high school, one of the guys was changing spark plugs in a van. He snapped off four spark plugs before telling the teacher! He was using a foot-lb wrench instead of an inch-lb! LOL! Teacher was not happy.

 

[busman]

I don't think you can use a wrench that is calibrated in ft-lbs for electrical; they are not sensitive enough. You need one calibrated in in-lbs.

Mark

 

[marmathsen]

I don't think you can use a wrench that is calibrated in ft-lbs for electrical; they are not sensitive enough. You need one calibrated in in-lbs.

Mark

What if I flip it over and use the Nm scale on the other side of the wrench?

Rob G - Seattle