Complicated Door Knob Replacement

I have an old house with glass door knobs. The bathroom knob no longer works properly. I bought a new replacement and when I removed the old knob, I noticed that the bore in the door is way too small for the new knob assembly. Should I get out a hole saw and cut a new hole? Looks like I can really screw this up if I'm not careful.

Reply to
finiteguy
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Bore a better hole, but clamp a board on the door and start your drilling through that to keep it from wandering off where it doesn't belong. Two boards, one on each side would be best so there won't be a splintery breakthrough. Measure carefully, and mark well before you start. God luck.

Joe

Reply to
Joe

The clamp-on jigs are for 2 1/8" hole saws - most definitely bigger than what the OP needs for his antique reproduction knob set.

Joe had it right. Drill the correct size hole in two pieces of scrap plywood, clamp one on either side of the door with the holes centered on the existing hole, and have at it with the drill. The escutcheon will mask minor errors.

R
Reply to
RicodJour

I think you're probably right and I probably read it wrong. My apologies.

R
Reply to
RicodJour

How much bigger a hole do you need? One way to enlarge a hole and keep it round and centered with vertical sides is to use a router bit that is larger in diameter than the bit shank. Extend the shank far enough through the hole so that the shank rides on the top portion of the hole thus cutting only a bit more than the bottom half; turn work over and repeat. When the last cut in the hole is the correct diameter, use a bit that cuts the same size as the shank to finish the cut.

As an example, if you start with a 3/8 bit on a 1/4 shank, you will enlarge the hole diameter by 1/8 with each cut. Whether or not you can get an exactly sized new hole this way depends on the sizes of starting hole and desired finished size; with a 5/16 bit on a 1/4 shaft you can get to within

1/16 regardless of starting hole size.
Reply to
dadiOH

I'm imagining that he has a door with mortise or tubular latches and is trying to replace with a modern lockset, something that always makes me cringe.

nate

Reply to
Nate Nagel

That was my first impression as well. OP has not posted back, so far, that I have noticed. If these are in fact old-style locksets, the backset will be wrong as well, I suspect.

I'd be looking on-line for repro knobs, or take out the entire assembly and start visiting salvage houses, as well as the oldest locksmith in town (sometimes, they keep junk boxes in the back room). In the short term, I'd steal the knob assembly off another door, to get the bathroom usable and buy some time.

Reply to
aemeijers

The replacement knob is a mordern knob that I got at Home Depot. The old glass knob is loose and the latch has a lot of slop. Feels like someday the knob will fail to turn the latch mechanism and I (or someone else)will get locked in the bathroom if it breaks.

Reply to
finiteguy

We would all be glad to help, but I think we need more information.

Is the old lockset a cylinder lock or a mortise lock?

If it is a cylinder lock with the hole in the door face too small: Bore the correct size hole in a scrap piece of plywood. Have the scrap piece large enough to be able to clamp it to the door face above and below the old hole. Carefully position the plywood for proper backset of the new lock. Let the hole in the scrap guide the drill into the door. A thin scrap on the back side of the door will prevent splintering as the bit goes through.

If it is a mortise lock, the problem is quite different.

I hope I guessed the problem about right, if not, clarify and ask again.

Reply to
DanG

You should take the new piece back and fix what you have. You can find old stuff to fit. No reason to bore new holes in old doors.

--Vic

Reply to
Vic Smith

actually if it is an old tubular lock they are still available rather than resorting to butchering a nice old door it can simply be replaced.

nate

Reply to
Nate Nagel

I might do that. I can take a knob from one of my closets and swap it. My house was built in 1947, I think its odd that they used these knobs during that time.

Reply to
finiteguy

From your limited description it sounds to be like you might have an old mortise style lock. Replacing that with a modern 2-3/8 backset lock is a big job that involves adding a filler plug to the door before you drill anything.

My advice would be to find another mortise lock if yours is broken. The glass knobs, the shafts and setscrews can be purchased at any full service hardware store.

I can and will describe the procedure in detail if you want to proceed.

Reply to
Colbyt

A woman might have wanted glass knobs. Some even have roses embedded in them. There used to be a wrecker's yard not far from where I lived that had everything you might want "old." Probably some source in your area. There's places on the net selling old stuff too.

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are probably steeper than you'd find in a salvage yard.

1947 was a good year. A very good year.

--Vic

Reply to
Vic Smith

The "Oops Arbor" from Lee Valley, while you didn't make the first hole but this will make the the new hole on center

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Reply to
PV

Here's a site that I found helpful. Hopefully it helps you the way it helped me. Good Luck.

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Reply to
Chele

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