DIY Home Improvement Forum banner

Installing interior door locks

1K views 5 replies 5 participants last post by  iamrfixit 
#1 ·
I have an interior door that I wish to change to a set of new locks.

The new lock calls for a round hole of 2-1/8" in diameter on the door slab, and 1" hole on the door edge. Pretty standard.

I took apart the old lock and found out the hole is only 1-1/2" in diameter, and the two screws that feed through the door, has their own small holes outside of the 1-1/2" hole.

I need to enlarge the existing hole to 2-1/8". Problem is I have nothing that I can drill into to center the hole saw to make a bigger hole. I think I can clamp a piece of wood on the backside of the hole and that may work.

The other issue is I have a set of hole saws and the closest to 2-1/8" is 2" and 2-1/2". Can I use 2-1/2" which is just a tiny tiny tad smaller than the cover plate of the locks? or is the 2-1/8" a rigid requirement?
 
#2 · (Edited)
You can pick up an inexpensive plastic jig made for drilling out door slabs for hardware. Usually they will screw right into the holes your latch plate screws into, with guides for both the holes. Irwin makes a decent one available at big box stores, hardware stores. I use these all the time for both new doors and situations like you mention, they are cheap, quick and easy to use.

Often the inch and an eighth holesaw will come with this kit, if not then it would be a good idea to buy one. I don't know if the bigger one would work or not, personally i'd buy the correct size, but that's just me.
 
#5 ·
The jigs that Chris and Joe mentioned will work fine, but so will your method. The way that you described is exactly how I did a few of the first ones I ran across, until I made my own jigs, but that was before big box store existed, and I'm not sure that any of the lumber yards had such a thing at that time. A lot of the Levitt homes of the 40's and 50's in our area have interior door latches similar to what you have.
 
#6 ·
Use an oversized piece of scrap plywood, then use the hole saw and drill a hole the correct size in it. You can then clamp it to the door and the plywood will guide the rim of the hole saw, no need to have material for the arbor to drill into. Having the hole already cut into the plywood makes it easy to position accurately. It is a good idea to have another piece of scrap clamped on the opposite side of the door, this way when you drill through it doesn't splinter the backside of the door. Found this video that demonstrates the method.

You can possibly get by with a 2" hole, depends entirely on the lockset. Some knobs will work with a slightly smaller hole but others require all of the 2 1/8". Don't use the 2 1/2" hole saw, that is too large and you will have problems with the knob moving around or not covering the hole. I recommend just getting the right size hole saw.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top