Rim lock sets were one of the earliest types of locks used in the home, and are also one of the easiest to install. They are installed on the face of a door and frame rather than being mortised into the door like modern lock sets. While a rim lock set offers a fairly low level of security, it can be used to add privacy and some security to interior doors or screen doors. Rim locks often have elaborate designs that can add a touch of elegance and history to the home. You can find these locks through antique dealers and some hardware reproduction companies.
Decide where you will place the lock set on your door. Because these locks are not really designed for security, they should not be used on exterior doors unless they are supplemented by an auxiliary deadbolt or other device. Once you've chosen a location, hold the lock against the door and lightly trace around it with a pencil to mark the location.
Remove the lock from the door and measure the location of the spindle and the keyhole. Transfer these measurements to the door and mark their location with your pencil.
Drill a hole to accommodate the spindle. It should be large enough that the spindle can freely turn in the hole.
Use your drill and chisel to create a keyhole in the door. Drill a hole at the top and bottom of the keyhole you marked in Step 2, then use your chisel to remove any wood left between the two holes. Remember that the key has to be able to pass through the entire door to reach the lock body, so test your key to make sure it fits before proceeding.
Install the lock body on the face of the door. Some rim locks come with fasteners, but many do not. You can use modern nails or screws, or find antique fasteners to match the look of your lock. The rim lock will usually have holes at each corner that are designed for fastening the lock to the door.
Set your strike plate. This device is used to catch and hold the latch, and was often called a "keeper" when used with rim locks. Place the strike on the face of the door frame so that the hole in the strike lines up with the latch bolt. It should fit flush against the lock body. Fasten with nails or screws.
Add the door knobs. The two knobs are connected by the spindle. Place one knob on each side of the door, with the spindle passing through the hole on the lock body. Some old knobs click together using an integral connector in the spindle. If yours doesn't, look for a hole in the base of one knob where a set screw can be installed. This set screw will hold the two knobs in place. Any small, modern set screw can be used at this location.
Install the rosette, or keyhole, on the face of the door that is opposite the lock body. It is used to give a finished look to the keyhole, and may consist of a decorative metal plate or a small keyhole-shaped unit. Use screws or nails to fasten this unit to the face of the door.
Modern locks require large holes to be drilled in the door. If your door has one of these holes, fill it in using several circles of plywood or hardboard. Add wood putty and paint to mask the hole's appearance. This will allow you to install a rim lock at any location you choose on the door.