In a message dated 1/3/2007 4:20:57 P.M. Pacific Standard Time,
> Back in my early days, we used extruded 6061-T6 in 2 inch diameter with
inch wall. Many of us sprung for the tubing and put as much os 20 feet of it
out the top of the tower. It seemed to hold up and I don't remember anyone
having any problem with it.
> That being said, I'm planning to put a tower with some HF antennae and I
found my old 24 foot 6061 mast in the barn. It's about 30 years old and
isn't even corroded. You know what I'm planning to do, so let me hear
why I SHOULDN'T use this. Especially after all the years of great track
record from the locals in southwestern Ohio.
Well, the thing you've got going for you is that the windspeed ratings
in Ohio are pretty benign. I think the top windspeed rating is 75 MPH.
The 6061-T6 has a yield strength of 35,000 psi - a pretty moderate
rating. I wouldn't have any problem with VHF/UHF stuff up there but it
handle an HF beam at the top. A typical tribander 10 feet up a mast can exert
50,000 psi bending moment without too much trouble so you can see the problem.
Water pipe is basically the same.
For more aggressive installations, you'll need some carbon alloy steel
tubing - e.g. SAE 1026, A520, etc. Your local steel supplier can give you the
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