skan wrote:Hi
I'm designing my own lock and I want to have somebody else build it (some company with CNC).
I need to know what tolerances are most commonly used.
If actually designing or building your own locks, take your own measurements. Don't listen to internet arm chair experts.
Put shims/feeler gauges next to keys and see how thin or thick of a shim or guage you can cram into the keyway along with the key. or.. measure keyway width, then measure factory and non factory key blank thickness and subtract and / by 2. As already stated, cheaper locks will have more play, while expensive locks (ASSA Twin) will seem like the key was custom made for that exact lock and there is little wiggle room.
I know you're looking for a quick answers but there isn't one. Every lock brand and keyway is going to be different.
Good Luck,
Squelchtone