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Tried a torque stick on a Cessna 172 wheel bolt and got a nasty surprise
I've used torque wrenches for years on landing gear hardware, but last Tuesday I figured I'd try a $45 torque stick off the Snap-on truck to speed things up on a tire swap. Set it to 100 foot-pounds like the manual says, and when I checked with my click-type wrench, one bolt was at 85 and another was at 115. The stick didn't even click or give any feedback, just let me keep turning. Learned that torque sticks are great for production car work but totally unreliable for aviation where you need that specific number every time. Has anyone else found a good fast method for torquing wheel bolts that actually stays accurate?
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violag806d ago
Your mileage may vary but torque sticks are basically just a spring in a tube, so they depend on consistent speed and technique from the user. In aviation, even the same bolt can have different friction values depending on how clean the threads are or if it's been lubed. My old instructor had a trick where he'd use a beam style torque wrench for the final check, since those don't drift out of calibration like click types can. For speed, maybe look into a digital torque adapter that gives you a beep when you hit the number, but still verify with a manual wrench every few bolts.
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robinp896d ago
85 and 115 is a solid 35% swing there. Sounds like you're playing torque roulette buddy. Maybe just flip a coin next time, might be more reliable.
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williamw756d ago
That's a solid point about the beam style wrench, I'd actually forgotten about that trick. @robinp89 mentioned a 35% swing which is wild, but even 10-15% spread from a torque stick can give you problems on critical joints. The digital adapter idea is good but I've seen those get knocked out of calibration if you drop them, so you're right to check with a manual one every so often.
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