Wood Door And Frame Preparation to Install A Key-In-Knob Lock

Proper Door Preparation To Install A Key-In-Knob Lockset
When installing a Key-In-Knob Lock (K-I-K) on an unprepared door many different factors come into play. Most locks sold today provide the purchaser with the ability to adjust the Backset of the lock. The Backset is the distance from the edge of the door to the center of the lock. The two standard backsets used today are 2-3/8" and 2-3/4". There is also the much less common 5" backset but this is usually a non-adjustable, fixed distance.

For lock surface placement, measure from the floor to the center of the lock. A height of 36 and 38 inches are the standard locations of a key-in-knob lock. Check the location of other locks throughout your home and locate your door surface drill point at a consistent height for aesthetic purposes.

IMPORTANT NOTE:
Measurement for the face bore should be made on the leading edge of the door
The leading edge is the first edge that meets the frame when closing the door into the frame. Preparing the door face to be measured and initially drilled on the incorrect face will make it nearly impossible to install the lock. In most instances, both sides of the door face are different widths. Most door edges are beveled so that the frame can properly accept the door as it is closed into the frame. If unsure, the narrower door width can easily be determined with the aid of a square against one of the door faces and the door edge.

Measuring For Door Template Location
Prior to drilling any holes, open and secure the door in place by driving 2 wood shims under the door from both faces. Take a measurement from the finished floor to the center of the lock. With a pencil, score a straight line across the edge of the door. Align the template that the lock manufacturer provided with the door edge center mark you just made. The template should have it's own center mark. This will properly locate the height at which the lock will be installed. Affix the template to the door with tape. Be certain to secure the template to the Leading Edge of the door. If the lock is supplied with an adjustable backset, the template will be marked on the door face for 2-3/8" and 2-3/4" backsets. Using an Awl and Hammer, tap a hole into the door at the designated marking for the correct backset. This will be the starting point for the pilot drill bit on the door face. It will also stop the drill bit from wandering. The portion of the template that wraps around the door edge also has drill point markings for several different door thicknesses. Determine the door thickness by measuring and select the proper drill starting point accordingly. Use an awl to tap a hole into the edge at the designated marking for your door thickness. Remove the template. You are now ready to bore the holes.

Bore Holes To Accept The Lock
Proceed to bore the door face employing a 2-1/8" diameter Deep Hole Saw. Drill into the door with the pilot bit until the hole saw just touches the door surface. Stop and ensure that your drill is level and square to the door with the hole saw. The holes you drill will not properly accept the lock if they are drilled on an angle. Drill into the door until the pilot bit just breaks the surface of the opposite side of the door face and no further. To complete the surface bore, drill into the door from the opposite face using the hole that the pilot bit created, as a guide. Once again, ensure that the drill is level and the hole saw is square to the door.

NOTE: Do not drill entirely through any door from one side. In the instance of a wood door, it will cause the wood on the opposite face of the door to splinter around the hole you bore. A metal door will be caused to bow out if drilled from one side only.

Being precise, bore a hole down the door edge using a 1" Spaded Bit at the mark you made previously. Once again, ensure that your drill is level as this will affect alignment of the latch to the lock handle.

Once completed, use the latch as a template. Place the latch in the hole on the door edge and line it up so the sides are square to the door faces. Using a pencil, draw the mortise lines around the latch and remove. Following the scribed lines and using a hammer and 1" chisel, mortise the edge of the door out to accept the latch. Once completed, place the latch into the mortised area and ensure it is flush to the surface of the door edge. Locate the center of the 2 fasten points in the latch and using a sharp pencil, mark each fasten hole for drilling. Drill out the holes and fasten the latch securely down to the door edge with the screws provided by the lock manufacturer. Do not simply drive the screws into the door edge as this will cause the wood to split. Insert the front and rear handle set through the door faces and fasten with the screws provided by the lock manufacturer. You have now completed installation of the lock.

Locating The Bore On The Frame To Accept The Extended Spring Latch
To locate the hole on the frame to accept the extended spring latch, with door open, use a tube of lipstick to paste down the latch extending from the door edge. Retract the latch with the door handle and keeping it retracted, close the door into the frame so it is firmly against the frame stop. Release the handle so that the latch strikes the door frame. You may need to retract and release the latch several times to result in an acceptable mark on the door frame. Once you have done so, retract the latch and open the door. You have just created a marking point to drill the frame by. Eye up the center of the marking. Using a 1" spaded bit, press against the frame with the tip and move the bit by hand to ensure that you will only drill into the frame avoiding the door trim. Drill the hole deep enough to accept the extended latch.

Use the manufacturer supplied strike plate as your template. From the side of the frame that the door closes into, line up the lip on the strike plate opening to the side of the drilled hole that is closest to you. Check that the strike plate is level. Using a pencil, draw a line around the strike plate. With hammer and chisel, mortise the wood out to allow the strike plate to sit flush into the frame surface. Locate the center of each screw hole in the strike plate and mark with a sharp pencil. Remove the strike plate and drill the two strike plate fastening points employing the appropriate drill bit according to the diameter of the screws supplied by the lock manufacturer. Drive the fastening screws through the strike plate and firmly fasten down. Close the door. The latch should drop into the strike plate hole.

TIP: In the event of misalignment of the strike plate, where the latch cannot properly extend into the strike plate hole, cut the heads off of 2 Golf Tees and drive them into the strike fasten point holes with a hammer. You can now proceed to relocate and drill the strike plate fastening points.

Required Tools:

1) Drill
2) Drill Bits
3) Deep Hole Saw (2-1/8" in diameter) and Mandrill
4) 1" Spaded Bit
5) 1" Chisel
6) Hammer
7) Phillips Type Screw Driver
8) Square
9) Awl
10) Installation Template (usually supplied with a new lock)
11) Wood wedges