I think 10 pounds atop a 4 foot pole that is only 1 1/4 inches will sway and
vibrate a lot. Probably crack the welds after a while. All the movement
will also mess up the radar image. If you braced it with guy wires it might
be OK.
Most of the commercial radar poles are 2 1/2 to 3 inch tubing. Do a search
on garhauer radar pole and edson radar pole. Even these use braces going to
the stern rails.

"Rob" wrote in message
om...
Hi,

I am looking to make a short hinged mast for a radar aerial from
aluminium tube for an inland waterways vessel. The aerial weighs 4.6
kg and mounts on a plate 210mm x 210mm. Was thinking of using a 1 1/4
inch 16 gauge aluminium tube, with a flat 10mm plate welded across the
top. Total mast length around 2.5m, with approx 1.25m above the
pivot.
Grateful for any thoughts.

TVMIA