1" drill bit to expand a hole

[kanling]

Replacing the door knobs on some interior doors. The latch hole on the edge of the door is now about 3/4 -7/8". The new hardware needs a 1" hole.

I need a 1" drill bit at a low price that I can use to enlarge the existing hole. A hole saw or spade-style bit won't work because I need it to self center in the existing hole.

The only thing I can find that might work is this Craftsman, but it is made for metal, my drill only has a 3/8" chuck, and it costs $26.

Anybody know any sources or a better idea of what might work? I haven't seen anything locally at all.

 

[Schmoe]

Get a paddle bit, hope that is not the same as a spade. If it is, just get the largest bit you can and "waller" it out.

 

[GMorg]

If you already have a hole, why not use a bur to grind it out some? In other words, make the current hole bigger. If you mark the hole first and grind to the line, you should stay centered.

 

[Matt_S]

That is the same thing, Schmoe.

Use a 1" hole saw with a centering bit in the middle. Drill a hole through a scrap piece of wood with the hole saw to create a template. Center the template over the old hole and either clamp or screw it in place, then use the hole saw to enlarge the old hole. I've used this technique numerous times to enlarge holes for new locksets.

 

[michaelc80]

As Matt_S said build a jig to go over the door with the 1" hole in the correct location. That way you can use a hole bit and know you'll be accurate. It's a little extra work but if it's worth doing, it's worth doing it right.

 

[Winston]

The Craftsman bit you linked to will work great.

I have also used the template method and it worked great too.

 

[kanling]

Matt_S, michaelc80... not a bad idea. Actually, I tried this before on a trial door and it was a significant PITA with the crappy hole saw I have. It didn't line up as well as I wanted. I was hoping a better bit would be a faster solution. Maybe there isn't one.

I could just go at it with a rat tail file, but since the backset is pretty deep, it would take a while.

 

[jmacmaster]

Use labman's technique, and of course use wood glue to keep the dowel in place while you're drilling the new hole.

 

[1sttruck]

Will one of those drum sanders that fits a drill work ? Use a coarse grade.

A pain, but you could also remove the door and use a drill press with the hole saw, which is perhaps one of the the 'right ways' to do it.

 

[labman]

Fill the hole with a 3/4'' dowel and redrill it with a spade bit. Might even whittle a peg out of a soft wood and use it. This also works when you need to move a hole over a little or reduce its size. .