How Does An Old Door Lock Work

The bolt is held securely in place by metal levers called tumblers 3 cut to various sizes to match the notches in the key.

How does an old door lock work.

The backset can be 2 3 8 or 2 3 4 in. The key to match the particular lock lifts the pins to the correct height to allow the latch the part that protrudes into the door frame to be pulled back against the spring allowing the door to open. Remove the cylinder plug from the cylinder the most critical part of this operation is removing the cylinder plug from the cylinder. Inside the cylinder are all the parts that work together with the key to lock or unlock the door.

You will require one wrench to apply tension to the lock cylinder and one long pick to actually get the pins of the lock to move. When the door is unlocked a part called a tang is resting fully inside of the cylinder. The spindle runs through the latch bolt which is inside the door perpendicular to the spindle. There are four parts to a mortise lock other than the mortise itself.

Differences between a mortise lock and a cylinder lock. Insert the old key and turn it either to the left or right. This screw should hold the knob securely to the spindle when you turn the knob. A mortise lock needs a mortise or a pocket in the door frame to operate correctly.

The key gold 2 is in a vertical position in the lock. The top of the cylinder contains pins and springs which keep pressure on the keyed pins. With the door locked the bolt gold 1 is extended into the mortise hole in the doorframe. Meet the mortise lock and door knobs.

Notice the set screw on the base of the knob on the right. Knobs spindle and latch a standard doorknob lock set consists of a pair of knobs one on each side of the door that are connected through the door by a spindle and held together by mounting bolts. Many locksets accommodate both. Because it uses the strength of the door frame a mortise lock is far more secure than other locks that attach to the outside of a door frame.

At the door edge use the template to drill a 2 in deep pilot hole for drilling for the strike or bolt. Mortise locks can function for decades in fact these locks are found in old houses and buildings and they have resisted the bad weather and time. The bolt of the lock fits into the mortise. Pilot holes through the door to center the 2 1 8 in.

This method should work on most pin and tumbler locks that people normally use. Mortise locks are very different and heavier than the usual cylinder locks and in its design they use lever locks as a mechanism. Using a drill with a bubble level or a torpedo level taped on top drill halfway through the door from each side with the hole saw to prevent blowout splintering. Once the key is removed the spring will automatically push the latch back out.

Key locks contain a small cylinder that runs down the middle of the doorknob and into the door. This mortise lock set is installed in a 1930 colonial in the boston area.