Bored cylindrical lock

– Typical preparation for installation of a bored cylindrical lockset includes boring two perpendicular holes into the door.
– The larger hole, known as the face bore, is bored into the door face, while the smaller hole, called the edge bore, is bored into the door edge.
– The edge may require additional preparation, such as routing or chiseling, to receive the latch assembly.
– Some commercially-sold doors may come prepared to receive bored cylindrical locks, such as entry doors requiring both a door knob and deadbolt.
– In the United States, the face bore is typically sized from 1.5 to 2.125 inches in diameter and is centered at 2.375 or 2.75 inches from the leading edge of the door. This distance is known as the backset.

– The cylindrical lock was invented by Walter Schlage in 1923.
– The bored cylindrical lock was developed as a more cost-effective alternative to the complex and expensive mortise lock.
– The mortise lock, still common in Europe, requires more labor-intensive installation and has a larger lock case.
– The bored cylindrical lock gained popularity due to its affordability and functionality.
– Schlage’s 1923 patent for the lock evolved from an earlier patent filed in 1920, which simplified door preparation compared to a mortise lock.

– No information provided.

See also
Mortise lock

– Gibson, Scott; Abram, Norm. ‘How to Install a Lockset.’ This Old House.
– ‘Door Repair Guide.’ Friday, 12 April 2019.
– ‘What is Backset.’ Direct Door Hardware.
– Derdak & Grant; Thomas Derdak; Tina Grant. ‘International Directory of Company Histories, Volume 82.’ University of California: St. James Press.
– USgranted 1674841,Schlage, Walter R.,Door Lock,issued 26 June 1928, assigned to Schlage Lock Co.Sources: