Dan S. MacAbre wrote:

Some of our doors have knobs, which we like (like idiots, we tend to
catch our sleeves on the ones with handles), but the problem with the
doors with knobs is that one's hand is a little too close to the frame
for 100% comfort :-) I wanted to fit some latches with longer backsets
(the 83mm ones seem about right), but they won't fit in the holes cut
for the existing latches. I need to enlarge them by a couple of mm.
I'm imagining that if I just try to offer the bit up to it, it will just
bounce all over the place, so I'm not going to try that. Right now, the
only thing I can think is to glue a bit of wooden pole in there and
start again. But is there another easier way, I could do it? I'm not
even sure that I could source the wooden pole/dowel of the correct diameter.

I did exactly the same job with one of the wood auger bits like the
second type on this page:

http://wiki.diyfaq.org.uk/index.php/...ers_0071-5.JPG

I started by filing the entrance to the hole so I could ge the first
couple of millimeters of the bit centralised, and turned it a few turns
using a strap wrench on the chuck before cautiously finishing with the
low speed on the power drill. It was still hard to keep it central, but
I'm useless at carpentry so it must be reasonably possible.




--

Roger Hayter