curve drilling

[pipeguy]

Hi all has anyone heard of curve drilling???? It is what it sounds like and applies primarily to draft holes. Any one know how this is accomplished thanx Bob Clark

[Jos]

Hi Bob,

Yes, I've heard of this technique - and more than that, I even own a pipe that is drilled that way. It's been made by german pipemaker Uwe Jopp. Some italian companies (Brebbia, for example) do that, too.
It's basically done with a curved tube, in which a flexible shaft is inserted.
In this german forum discussion http://www.pfeife-tabak.de/phpBB3/viewt ... 5&start=0. the question is discussed, too.
The discussion is uninteresting, but there's some nice drawings from old patent files ...

Regards, Jens

[Sasquatch]

Ser Jacopo, Ashton, Luigi Viprati... lots of makers do it. The chief disadvantage is that most of the tools leave quite a large hole - 1/4" or so, and some of them leave a poor quality path. My Ser Jac is smooth as silk, but at least 1/4" bore and maybe 5/16.

What it amounts to, as noted above is a sheath of metal that is curved, with a flex-shaft cutting head at the front. It just "drifts" as it cuts.

[e Markle]

I'm pretty sure Angelina Jolie can curve drill bits in mid cut. Other than that I think it's impossible.