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Posted to rec.crafts.metalworking
Andrew VK3BFA
 
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Default Whats it called, how do I make on?

Hi All,
new to this metalworking stuff, so please excuse my stupid newby
questions. I am trying to build an HF Yagi antenna from telescoping
aluminium tubing(to reduce windloading and weight) - trouble is,
Imperial size tubing was a good fit into the next size ID, so
telescopic sections could be made easily. All thats available now is
Metric sizing, and its too sloppy a fit into the next size up. HOW do I
roll/reduce the diameter of the bigger tubing so its a nice
interference fit onto the smaller size down? - whats the machine
called, can I homebrew one (I have basic hand tools, a welder, lots of
"stuffit - lets try this"...misguided enthusiasm -- well equiped
here...) - any tips, references. pointers appreciated.

PS I built the tower its going on, 8.5 metres, teaching myself to weld
as I went. Welding gets better as you go up.......so, the next logical
step is to build the antenna that goes on top of that.........

Andrew VK3BFA.