On Tue, 8 Feb 2005 18:03:14 -0500, "ATP*" wrote:

For the drills with the oil feed holes parallel to the shank, which run from
one end of the drill to the other, is a different bushing made for every
diameter of drill? Also, is the oil fed under pressure? I was contemplating
settting up something to use oil-fed drills in the tailstock of my lathe.
I'm finding a lot of stuff about the drill bits themselves, but not much on
the equipment needed to run them. TIA.

It appears that you are describing a gundrill. If this the case the
yes, a bushing is used for every drill size. This bushing guides the
drill point as it enters the work and must touch (usually) the surface
of the work. The shanks for different groups of sizes of drill are all
the same size where the drill is mounted in the spindle. The oil
pressure can be up to 3000 psi. The oil forces the chips out of the
hole and actually supports the drill when the drill is a small
diameter. If you are seeking information about a different kind of
drill please post a link.
ERS