Mortise Cylinder

  This is the threaded cylinder found in mortise locks, some panic devices, Adams Rite glass and aluminum door locks, and a lot of electric key switch applications, such as apartment garage entry. The better quality cylinders, off brand (shown here) or brand name are milled from a solid brass bar. I encounter a fair number of very cheap die cast cylinders, some of which come installed with very expensive aluminum and glass storefront type doors. When I run into one of those I switch it out with a solid brass version. Expect to pay $15-$20 minimum for a decent solid brass off brand cylinder. Name brand and high security cylinders are also available. The good thing about using mortise cylinders is that as long as you have the correct cam, you can use any brand or keyway cylinder in any other brand or type of lock that accepts a mortise cylinder. This makes it possible to use, for example, a Schlage cylinder in a Sargent or Yale mortise lockset. The brass threads on these cylinders are delicate, and care should be taken when installing. If the the hole in the door and the threads in the lock body are not in proper alignment, the lock body threads are damaged, or the lock body itself damaged, it can be difficult to install one of these cylinders. Images at left show a typical mortise lockset and mortise cylinder.

 

  The images below show the cylinder partially inserted in the mortise lock body, and the set screw in the lock body lining up with the groove in the cylinder. If the set screw is not lined up properly, it will not sufficiently hold the cylinder in place. The lock will probably not function correctly if it is not lined up, as the cam on the rear of the cylinder will also be out of correct position.