I’ve always wondered about the S&G adjustable-torque locks. One impression is that this was required by the DOD to meet mil specs (e.g. to resist a vibration attack) but I can’t remember where I read that. To do this properly you’d need a torque meter, a collection of clamps for all of their various dial shapes, and clear instructions (e.g. measure the torque with just the drive cam moving, or all three wheels moving).
Does anybody else (Mosler, Diebold, La Gard, …) have a torque adjuster? I don’t recall seeing this outside of Sargent & Greenleaf.
FWIW the patent is US 4,163,376 (1979).
I’ve never seen the adjusting kit in S&G literature and after watching eBay for many years I’ve only seen a kit for sale once. This tells me hardly anybody uses the adjusting feature and those who do probably just do it by feel. Another solution in search of a problem?
