KEYS

On 25/04/2011 04:37, Vincent Slyngstad wrote: You've apparently misplaced the decimal point :-) A 0.8" cut, which is over 3/4", would be longer than the key's tube... Here's what I got from two original XX2247 keys: tube OD 0.377" (9.58mm), tube ID 0.310" (7.87mm). The cuts are arranged in 7 out of 8 evenly-spaced positions around the outer circumference of the tube[1]; the eighth position is occupied by a rectangular-section key approx 1.5mm wide, and 1mm deep inside the tube, about 1.3mm high on the outside. The outside part of this key is short, extending from approx 0.8mm from the end of the tube to about 3.6mm back, while the inside part extends almost the full length, from about 0.8mm inside. [1] I've got other tubular keys where the cuts are on the inside of the tube. The cut depths, clockwise from the first position, looking into the open end with the key at the "twelve 0'clock" position are: Key 1 Key 1 Key 2 Key 2 0.0770" 1.94mm 0.0785" 1.95mm 0.0150" 0.37mm 0.0155" 0.39mm 0.1055" 2.68mm 0.1070" 2.72mm 0.0435" 1.13mm 0.0455" 1.13mm 0.1075" 2.72mm 0.1085" 2.74mm 0.0780" 1.96mm 0.0785" 1.98mm 0.1075" 2.72mm 0.1095" 2.77mm These are actual measurements from a depth micrometer. As you can see if you do the conversions, it's not easy to get consistent results; the ends of the keys aren't perfectly flat. Key 1 has "Chicago Lock Co", "ACE" and "DO NOT DUPLICATE" stamped on it (the last in quite small letters). Key 2 looks older but has the same legend, slightly differently arranged. For comparison, here are the depths from a different key, Chicago Lock Co ACE XX4306: 0.1070" 2.72mm 0.0775" 1.97mm 0.0600" 1.53mm 0.0615" 1.56mm 0.0180" 0.45mm 0.0780" 1.97mm 0.0780" 1.97mm I'm not quite sure what this says about cutting tolerances or what multiple the depths of cut are. -- Pete Peter Turnbull Network Manager University of York