Door knob hole size discrepancy

janralix said:

Or am I stuck with trying to enlarge the holes by [1/16"]?

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Two ways that come to mind.

Grind the hole larger with a rasp or abrasive drill-powered metal drum.

Put a wooden dowel into the latch hole. This provides a center for a 2-1/8" hole saw. Once the larger hole is started you don't need the centering dowel. For only 1/16" this might not work.

In some cases a perfectly round hole is unnecessary. It may be possible to form a somewhat oval hole to allow the guide pins to be inserted.

I run into this every now and then and have found the easiest thing to do is drop a smaller hole saw measuring the diameter of the existing hole into a larger hole saw that is the desired diameter. The smaller hole saw then acts as a guide for the larger hole saw.

Clamp a piece of 1/2 plywood to the door, flush on the edge on the high side of the bevel. This is the side of the door opposite the stop. Lay the template from the new lock on the plywood and mark the center of the 2-1/8" bore. (Should be 2-3/8" from the edge of the door and plywood). Make sure it's at the same height and centered with the latch bore in the edge of the door. Drill through the plywood and the door with the new size holesaw. When you are half way through the door, clamp a fresh piece of plywood on the opposite side of the door and finish drilling. Otherwise, you'll splinter the face of the door when the holesaw breaks through. Yes, you'll need a 2-1/8" bore for a Schlage lockset. Yes, it is one of the better quality locksets out there.

I've done something similar to what M6 describes. I have a piece of 3/4" plywood already drilled with a 2 1/8" hole set for the 2 3/8" backset required for most locks. I also clamp it to the door, drill halfway through, then switch it to the other side and finish the hole.

I've found that Schlage locksets are very picky about being bang on with the hole size and cause alot of grief. I've found that Weiser locks are much more forgiving and allow more room for error.

If you're set on Schlage, I would use the method mentioned above - place a 2 1/8" holesaw over a 2" one and use it as a guide.

i usually just run the laminate trimmer around the hole.....rarely do you need the exact size for the machanism ...just for the trim ring....