Jeff Dieterle wrote:
Where do I find the galvanized bolts with the spline under the head to
assemble a 3-leg tower??



I go to http://www.fastenal.com/ for real hardware but I don't know if
they have exactly what you desire.

W8LNA

McMaster Carr at mcmaster.com has a lot of hardware too.

Is the SHAFT of these bolts splined near the head? Never seen those,
but it sounds like a good idea.

There are ones with the serrations on the bottom of the head itself.
McMaster has those, they're pretty common.

Dan
N3OX

common bolt

just like lug bolts used on your car to hold the weel on the hub.