Smitty Two wrote:

Anyway, I can see you like the bolts. You could make your own clamping
fixture, a combination of the V-block idea and the two by four idea. If
you have a table saw, you could cut stepped grooves in two 6 or 8 inch
long wood blocks. The inner step has a width and depth of 1/2". The
outer step has a width of 1" and a depth of 1/2." Drill some holes for
drill bushings, available at the industrial hardware store, press them
in, clamp the two halves around the three tubes, and drill.

If you're going to do all that cutting on a table saw, then just set the
blade at a 45 degree angle and run a block through twice so that it cuts
a nice V. If you use a 2x4 block, set your fence at about 2.25" from
center and you'll get a 1/2" wide V. Drill a couple holes to bolt it to
the drillpress table. It won't be a permanent tool, but it'll work
perfectly to build one bike.

A further enhancement, I welded a short piece of angle to a C clamp.
Makes holding the tube much easier.

--
This is by far the hardest lesson about freedom. It goes against
instinct, and morality, to just sit back and watch people make
mistakes. We want to help them, which means control them and their
decisions, but in doing so we actually hurt them (and ourselves)."