carl mciver wrote:

Ah, very good idea. The thru pins I will be using a lot elsewhere, but
a set screw in conjunction sounds excellent. Welding a nut on the outside
for a set screw is a great idea, but that reminds me of the question that
came up the other day: Concerning welding nuts on, what is the best way to
get it square, not cook off the threads or otherwise damage the nut, and get
it exactly where you need it to be? Working with stick here. Last time I
did one with a torch it turned out to be a royal PITA.

I use mild steel square nuts without a finish. They are often
greasy and need to be cleaned. I am usually attaching to an angle
leg or a piece of square tube. Use flat bar the same size as the
angle or tube, drill it out to fit the bolt, and then chop off a
nice square piece with the hole in the middle. This forms the base
of the leg.

For jigging, I run a bolt with another nut on the back through the
hole and screw the nut to be welded on. the first nut can then jamb
everything tight once the nut to be welded is positioned where you want
it. That way everything stays put while you weld. When you're done, just
loosen the first nut and thread the bolt out. Reuse on the next piece.

The square complete with nut then gets welded to the bottom of your leg.

The square nuts are nice and meaty. They are flat on one side and
sort of rounded over on the other. The rounded side goes against
the square piece with the hole in it. This gives the equivalent of
a V-groove to weld.

1/4-20 nuts welded to a washer for 3/4" round tubing are quite
challenging. You have to make sure the weld doesn't interfere with
the leg--otherwise you have to grind to fit.

Hopefully this is clear.

Jeff Dantzler