. your probably confusing them with brand names, your not going to be able to buy Aircraft grade ally from a metal shop.. try finding a Capral Aluminium distributer in a capital city. The T8 sections i mentioned before come from them .
a 30+% carbon mast , with an insert in the lower 0.5 m would probably surfice

Hi,
I noticed this post, I have been buying high tensile tube , firstly for gryocopters. airborne trikes and now land yacht masts, for a few years from Bob Kiely
(Light Spars Of Austrlia
6 Horscroft Pl, Moorabbin,
VIC 3189
p: (03) 9555 4622 f: (03) 9555 4965)

Bob still only uses phone / faxes ( as he says he is still using carrier pigions)
Bob has supplied masts for Travis Bartlet(through a supplier) and 2 directly to me.
He tests the tenstile strength of all his tube before he lets it go.
He is a great guy and has had years of experience in making masts .

I think that is the outer drill rod tube thhat you have got hold of is is a bit on the heavy side. most of us use the lighter inner drill tube.
Cheers
Aus 230

www.seabreeze.com.au/forums/Land-Yacht-Sailing/Construction/masts/?page=1

sounds more like a rod from a raise bore