TIL I was torquing bolts wrong for years because of a bad habit

I was working on a Cessna 172's landing gear assembly last month, putting in new bolts. I've always done it by feel, you know, just going until it 'felt' tight and then giving it a little extra. My lead, Mike, was watching me and just said, 'You know that click you're waiting for? You're not letting it happen.' He made me use his Snap-on torque wrench on a bolt I'd just done. It clicked way before I thought it should. I'd been over-torquing by a solid 15 foot-pounds for years, just muscle-memory from working on cars. It hit me that I was treating aircraft like autos, and that's a fast way to cause a stress crack. How do you guys break a bad habit like that, especially one you didn't even know you had?

3 comments

3 Comments

the_charlie26d ago

My old shop made us re-torque ten random bolts every Friday to break that exact habit.

perry.jessica26d ago

Force yourself to use the torque wrench on every single bolt for a month, even the ones that feel stupid to check. I had to do that after I kept over-tightening spark plugs. It feels slow at first, but you build a new feel for what the right tension actually is. After a while, your hands just know the difference and you can trust yourself again.

hugo_nelson9d ago

Combine that with marking the wrench handle with a paint pen at the right spot. The visual cue plus the physical action rewires your brain faster. Did that for lug nuts and now I can set them within a few foot-pounds just by feel.