Steven Swift wrote:

I was thinking that I could build a support by screwing together 10ft
lengths of this galvanized iron pipe. Start with 1-1/2inch on the
ground, use reducing couplers until I am down to 1/2inch at the top.
Seems pretty strong and stiff. The wire load would be pretty minimal
(we don't get ice storms very often). I could get 30-50ft really easily.


It's not a good idea. Even a slight wind puts a load on the wire. Think
about a first class lever. There will be about a thousand to one
multiplication of the wind force on the wire at the first thread coming
out of the coupling/reducer. You basically have a ten foot lever with a
fulcrum at an inch and a half from the far end. The metal isn't that
great of an alloy to begin with and gets weakened further by the cut
threads. The breakage will most likely happen at the bottom of one of
these threads. Don't do it...


mike

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..let the cat out to reply..