Miki wrote:

I tried searching, but couldn't seem to come up with the correct search
term. I'm quite sure this has been discussed though.

If you have a tube with a hole drilled in it radially, and want to
drill more holes exactly in-line with the existing hole, how would you
do this on a drill press? Finding the center of the tube is the easy
part, but how do you know you have the tube "clocked" correctly on the
V-block?



I think what you are asking for is all the holes to be parallel, ie. no
twist
of the tube allowed between holes. SO, you need to keep the tube from
twisting between holes. Clamping anything to the end of the tube that has
a flat side on it would work, as long as it doesn't run off the end of
the drill press
table. That could be a problem. One scheme would be to have a block with a
vertical hole in it clamped to the table. For the first hole you drill
the tube.
Then, you move the tube to the next position, and stick a pin through the
first hole into the block, and clamp the block in place on the table.
For each
successive hole, you move the tube, and repin to the block. You'd get
repeatable
alignment of the holes. There would be cumulative error on twist,
depending on
how accurate the pin fit the tube and block. But, this is likely good
enough for
most instances.

Jon