Why Locks Fail: What Is Actually Happening Inside the Mechanism
Most lock faults trace back to one of a handful of root causes. Worn or corroded internal components are common in older properties — the springs, levers, cams, and follower that make up a mortice lock repair or rim lock repair job have usually been moving thousands of times a year for decades. When a spring loses tension or a lever drops out of alignment, the key still enters the barrel but cannot complete its arc. Grit, paint overspray from a recent decorating job, or a build-up of old lubricant that has turned tacky will cause the same symptom: a barrel that turns stiffly or not at all. On multipoint uPVC doors — extremely common across Hackney's newer housing stock — the gearbox that drives the hooks and rollers is a frequent failure point, and a stiff or non-lifting handle is almost always the first sign that the gearbox is failing internally.
Misalignment is another major cause. If a door has dropped on its hinges (very common with heavy composite and timber doors in older Hackney properties), the bolt or latch no longer lines up cleanly with the keep plate in the frame. Every operation forces the bolt to drag against metal, accelerating wear and eventually jamming the mechanism entirely. Euro cylinders that have been poorly fitted, or that are the wrong length and protrude beyond the door furniture, are also vulnerable to being snapped — a known attack method — and a cylinder that has partially snap-damaged internally will feel stiff long before it fails completely. Our technicians carry anti-snap, TS007 3-star rated cylinders and can advise whether a replacement cylinder is a smarter long-term answer than a repair.