Found a trick for torque wrench calibration using a fish scale and a pipe

My digital torque wrench was reading way off on A320 landing gear bolts. Tried the homemade calibration method with a 2-foot pipe and a bathroom scale - ended up within 2 ft-lbs of the shop's $500 tester. Anyone else ever rig up a field calibration that actually held up?

2 comments

2 Comments

shane_williams25d ago

Heard a guy from one of the aviation forums mention doing that exact trick with a fish scale on a Cessna brake caliper bolt. He said it saved his butt on a Sunday when nothing was open and he had a brake job due Monday morning. I bet that bathroom scale method is fine for most stuff, but I'd still double check it against a known good tool once in a while. Those cheap digital wrenches drift like crazy after a few months of hard use, so a quick field check beats guessing.

ben40225d ago

That field check tip is solid. I've seen those cheap digital torque adapters lose their calibration after a couple of months of weekend use, nothing crazy. My buddy runs a small shop and he keeps a beam style torque wrench as his "truth" tool just for this reason. He'll take a reading on his digital wrench, then check it against the manual one to see how far off it is before he trusts it on a customer's car. The bathroom scale method is clever for a quick sanity check, but it's not something I'd rely on for anything critical like head bolts or suspension work. You're right, double checking against a known good tool once in a while is the smart play.