"wright1902glider" wrote in message
oups.com...

Suggestions? Methods? Tools?

Harry.............

Drilling in a Vee block with a clamp is, of course, the way to hold the
tubing. On larger tubing, lining up the holes by placing a piece of angle
iron on the tube and using the edge of the iron as a straight edge to scribe
a line works pretty well.

When I was a nipple twister in the pipe shop at Todd's shipyard, we had some
clamps made especially for operations like this. It was a two-bolt pipe
clamp that bolted tightly around the tube. Welded to one half of the clamp
was a short piece of 1" x 1" angle iron. It was welded across the diameter
of the tube and parallel to the clamp.

With the tubing clamped in a drill press (or in a tubing bender), a level
was placed on the angle iron and the clamp rotated until the bubble was in
the center. The clamp was tightened at that point and either the first hole
drilled or the first bend made.

Then the tubing was relocated for the next hole (or bend). This time, you'd
rotate the tubing until the level showed that in was in the same orientation
as the previous setup. Clamp the tubing in place, drill or bend and move on
to the next.

You could also rotate the tube from one operation to the next by any degree
if you used an adjustable degree level.

Regards,
Rich S.