Lock Rekeying: step by step

A rekeying visit follows a straightforward order. First the locksmith confirms you are entitled to change the locks, which for an owner is identification and for a tenant includes the landlord's agreement. Next comes a walk around the house to list every door to include, read the keyway on each cylinder and check its condition. The cylinders come out one at a time, are pinned to the new key and go back in. Every door is then tested with the new key and with the old one, spares are cut and tried in each lock, and you receive a note of what was done.

Reading the keyway on each lock

Whether several doors can share one key depends on the cylinders, not the number of doors. Each lock has a keyway, the profile a key must match to enter the plug, and only cylinders with the same keyway can be pinned to the same key. The locksmith looks at the face of each cylinder and the profile of each existing key to sort the house into families. Most homes carry one or two of the common residential keyways, sometimes with an odd one on a side door or a padlock. Anything from a different family is noted so you can decide whether to swap that cylinder for a matching one and bring the door onto the house key.

Bringing several doors onto one key

Keying doors alike is the same operation repeated with the same new key. Once the first cylinder is pinned and proven, the locksmith removes the second, follows the plug out, and loads bottom pins to the identical depths so the same key operates it, and so on around the house. Where a door carries a cylinder from a different keyway family, that cylinder is exchanged for a matching one in the same finish and then pinned to the house key. The result is one key on your ring that turns every exterior door, with the individual locks unchanged in appearance and function.

Looking after a freshly pinned cylinder

A cylinder that has just been rekeyed turns as smoothly as it ever will, and a little care keeps it that way. Once or twice a year, a puff of whatever lubricant the cylinder maker specifies into the keyway and a few turns of the key is all it needs, since some current cylinders use oil while too much graphite can itself gum a cylinder. When you need more copies, cut them from one of the locksmith's originals rather than from a copy, because each generation drifts a little from the true depths. A key that starts to need a jiggle is the cylinder asking for a clean and a new key, not a sign of anything serious.