Since I know the drill, so to speak, when going through metal detectors I have been quite fortunate the past few years not to set anything off and thus be subjected to secondary. That was true until my delightful day at LAX. No pen, money clip or change and I still set off the detector. What was most amusing was the stares of, most likely, less frequent fliers as I was being patted down. Anyway, I guess it is too much to ask our wonderful TSA to have standard calibration standards for the metal detectors at all US airports