I think Stan´s quide will work
I have my HiZ veticlas that are shorter, starting with 1.5 inches x 0.065
wall uf for several years in a windy location and with no guys
So starting 2 x .0120 I think will be very good, no less that that
73,
Jorge
CX6VM/CW5W
El mié., 1 ene. 2020 a las 22:57, Stan Stockton (<wa5rtg@gmail.com>)
escribió:
> Gedas,
>
> DXE has .120 wall aluminum tubing in the larger sizes that skips every
> other 1/8" OD size when telescoping.
>
> I would start with 3 feet of 2 inch X .120, then 6 foot pieces of 1.75,
> 1.5 and 1.25 (all .120 wall) and then 3 foot pieces of every size they have
> starting with 1 inch down to 3/8. You won't be using 3 feet of the 3/8".
> This is good for about 80 mph and will end up weighing about 18 pounds.
>
> Less expensive and even lighter weight would be to start with a smaller
> size and use longer lengths of smaller diameter stuff at the top. How
> strong do you want it to be? If the wind speed is more than about 65 MPH
> at that low height through the trees you probably have bigger problems than
> a bent 40m vertical.
>
> 73... Stan, K5GO
>
>
>
> > On Jan 1, 2020, at 10:13 AM, Gedas <w8bya@mchsi.com> wrote:
> >
> > HNY to all !
> >
> > I cannot think of a better time to start a new 40m phased vertical
> project then the dead of winter with snow on the ground (as usual I could
> not get to it during the summer or fall).
> >
> > Anyway, I have drawn up two possibilities for a pair of 33' self
> supporting verticals. Both start out with a 10' length of EMT but one
> choice starts out with a larger dia then the other before I switch over to
> tapering aluminum sections.
> >
> > A) Starts out with a 10' length of 1-1/4" EMT followed by tapering 5'
> sections of aluminum tubing (4' long exposed, 1' inside the previous lower
> section) until the very top length section which will be 3/4" OD dia. These
> will be standard DX engineering aluminum tubes.
> >
> > B) Starts out with a 10' length of 1-1/2" EMT, then a 5' length of
> 1-1/4" dia of EMT (4' long exposed, 1' inside the previous section of EMT)
> then followed by tapering 5' sections of aluminum tubing as above. The only
> difference being this choice would end up using 1" aluminum tubing as the
> very top piece.
> >
> > So the obvious difference between the two are that choice A) uses just
> one length of thinner EMT and overall thinner aluminum tubing sections to
> the top while choice B) uses 2 lengths of larger dia EMT and then larger
> dia aluminum tubing to the very top.
> >
> > I do not have the software to analyze choice A) vs. choice B) in a high
> wind situation. I am uncertain if the stronger, larger dia tubing with it's
> higher wind load will be a plus or a minus in the end to it's overall
> strength. Any thoughts or comments on which one will survive better during
> heavy wind conditions? TU
> >
> > Gedas, W8BYA
> >
> > Gallery at http://w8bya.com
> > Light travels faster than sound....
> > This is why some people appear bright until you hear them speak.
> >
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--
73,
Jorge
CX6VM/CW5W
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