Replacing Locks Replacing Locks
1. When installing a better quality lock it may be necessary to deepen the latchplate mortise a bit to enable the faceplate to sit flush with the door. Use your chisel with the same care as described in Step 7 previously to adjust the mortise area.
2. The template furnished with the new lock will enable you to determine whether the hole on the face of the door is of the proper diameter to accept the replacement lock. A wood rasp can be used to enlarge the hole to the appropriate measurement.
3. The existing strikeplate can usually be left in place, although you will want to replace the screws with those that are 3 inches in length. Check the hole to be sure it is deep enough to accept the new latchbolt. It must also be in the proper position to depress the plunger on the deadlocking latch. If you choose to replace the strikeplate assembly, you can find additional hardware on the market today that is stronger and more resistant for this purpose.
4. You can reduce the gap between the door and the frame by placing a cardboard shim behind the strikeplate. Again use 3 inch screws.