Originally Posted by HillRider
That "elbow calibration" can take a long time to develop and is particularly suspect for the new mechanic. I think nearly everyone is shocked by how much force getting crank arms and bottom bracket cups torqued to specification require. A lot of loose cranks and bottom brackets have happened because of poorly calibrated elbows. A lot of snapped 4 mm screws too. For the experienced mechanic, no problem. For the nooby, buy a torque wrench.
To quote an old Car Craft article from at least twenty years ago, "if you think you were born with a calibrated wrist, you are sorely mistaken".
While it's certainly possible - with experience - to get a feel for when you are about to tighten something beyond the breaking/stripping point, I've yet to see anybody who can accurately ballpark a given torque specification while working blind.
-Bob