"James Waldby" wrote in message
. ..

OP 21 Sept 2009, Michael Koblic originally described the problem via:
"I tried to drill a 3/16" cross-hole in a small steel cylinder
(0.3125" diameter, 0.400" length). I clamped the cylinder by the
ends (faced-off and therefore parallel) in a fairly substantial
drill press vise..."

The length of the part, .4", less the hole diameter, .1875",
is .2125, so using two vises for this part would clamp only about
.11" of material at each end. It would be better to make a jig to
hold the part for cross drilling.

The jig would have a horizontal 5/16" hole to hold the part and
an intersecting vertical 3/16" hole for cross drilling.

If the jig were split vertically and hinged at the bottom, it
would clamp the part when clamped in a vise.

If the jig were split horizontally and clamped with vertical
screws or with C-clamps, a hardened drill guide bushing could
be pressed into the top half of the jig, or the jig itself
could be hardened.

If making only a few parts, don't bother splitting the jig, just
drill the intersecting holes and start drilling parts. Once the
drill bit enters the side of the part, the part won't shift within
the jig.

Others suggested exactly that. I was hoping to get away without having to
spend time making a jig as this was a one off part of an experimental
design. However, as the procedures are beginning to take shape I see that I
shall have to make not just one but several of these if I cannot make Don's
method work on my existing vise.

--
Michael Koblic
Campbell River, BC