Installing a Lockset

Determine the best height for the lock. The lock comes with a paper template. Fold the template and tape it to the door. Select a 2-3/8-inch or 2-3/4-inch backset. Use an awl or sharp nail to poke a small hole at the center of the cylinder hole on the face of the door and the latch hole on the edge of the door.

Insert the tip of the hole saw's guide bit into the awl hole. Drill, taking care to hold the bit level and at a right angle to the door. (Guides are available; see below.) Stop when the guide bit pokes through the other side. Drill from the other side to complete the hole.

Switch to a spade bit and drill the latch hole through the edge of the door, using the awl hole as a guide. Drill all the way into the cylinder hole. Some locks call for continuing to drill on the other side of the cylinder hole. Clean away sawdust.

Insert the latch into the latch hole and temporarily anchor it with screws, with the bolt centered in the hole and the latch's plate centered in the door edge. Mark with a knife for cutting the mortise around the plate.

Use a hammer and a sharp chisel to cut a mortise in the edge of the door. First use the chisel to cut the lines about 1/4 inch deep. Then chisel from the hole outward.

Insert the latch into the mortise and check that the plate will be flush with the door edge. You may need to remove the latch and chisel a bit more. If the plate is set too deep, insert small shims. Drill pilot holes and drive screws to attach the latch.

Insert the inside portion of the lockset -- the one that has a tab that fits through the latch -- until it rests flush against the door. Insert the other portion and drive screws to attach the two. This can sometimes be tricky; have a helper hold the inside portion while you drive the screws.

Slide the latch bolt partway out and gently close the door. Mark the edge of the jamb for the vertical center of the bolt. Use a square to transfer this height to the inside face of the jamb, and mark for the horizontal center, which is half the thickness of the door.

If you are installing a standard bolt, you need drill only one hole. To install a security strike box, mark the outline of the box and drill two holes, one above and one below the mark.

For a security box, chisel out the area to create a rectangular hole.

Close the door and check that the bolt slides easily into the hole. Temporarily attach the strike plate and mark for the mortise with a knife.

Chisel the mortise as in step 5, but make it shallower. Insert the strike box (if any) and secure it with screws. Close the door and test that the latch slides easily into the hole.

Attach the strike plate, drill pilot holes, and drive the mounting screws.

Test the lock again. If the bolt does not slide easily into the strike, try tapping the strike with a hammer and screwdriver. Or you may need to file or move the plate.