Why Keys Snap — and Why It Matters for Your Lock
Keys break for predictable reasons: metal fatigue from years of daily use, a lock cylinder that has become stiff due to a lack of lubrication or debris accumulation, forcing a key that was already bent, or using a worn duplicate that was cut slightly off-spec. Chicago's climate accelerates the process — freeze-thaw cycles cause door frames to shift, putting lateral stress on keys every single winter. When a key finally snaps, the break point is almost always inside the cylinder, not outside it, because that is the narrowest part of the keyway where torque is greatest. The fragment can sit flush with the face of the plug, sit deep inside the cylinder, or — in the case of an automotive ignition — lodge behind the wafer stack entirely. Each scenario requires a different technique and a different set of extraction tools, which is why a professional assessment matters before anyone starts probing around inside your lock.
The lock or ignition itself is not automatically ruined when a key breaks inside it. Whether it survives intact depends largely on what happens next. Attempts to dig the fragment out with a bobby pin, a pocket knife, or a screwdriver blade frequently score the soft brass of the cylinder walls, dislodge the driver pins out of their correct positions, or push the broken piece deeper into the housing. If the cylinder is damaged during a DIY extraction attempt, what started as a straightforward broken key extraction job can turn into a full cylinder re-key or replacement — adding time and cost to an already stressful situation. Our technicians assess the fragment's position with a light and a pick probe before touching it, so the approach is deliberate rather than experimental.
