On 11/28/2017 12:04 PM, Valeri Galtsev wrote: > Thanks, Lamar! that is very instructive. You're welcome. > I was always unimpressed with > persistence of attempts to make more secure (less pickable) cylinder cased > locks (precision, multi-level, pins at a weird locations/angles). The best way to make an unpickable lock is to make the tolerances of the pins and the cylinder bore as tight as possible, since picking relies on part tolerances to work. But several sidebar designs are out there that are pretty hard to pick, including Schlage Primus, the various Medeco styles, and others, such as the Kaba dimple locks used on Cisco Metro 1500 DWDM gear for power switches (the lasers are powerful enough to permanently damage your eyes in short order in those). > Whereas > there exists "disk based design" (should I say Abloy?), ... I had an old Bell System payphone with Abloy locks. Very difficult to bypass or pick, and requiring very different techniques than are used with pin-tumbler locks. There were two locks: one on the coin door (activated four large rectangular bolts, one on each side, with the only common point that could be successfully drilled being the lock cylinder itself), and one on the door to the circuitry (which included the programming port to set the per-call rate for use with a standard subscriber line, instead of the dedicated pay lines, as well as the coin-counter electronics). They were used on many payphones twenty years ago or so.