larryjspammenot@teleport.com wrote:
> I was particularly interested in the construction of the 66' DX
> Engineering vertical, not to use as an actual vertical antenna, but
> to mount in a tripod on my roof and then use it as a tall support for
> an 80M inverted vee. I figured an aluminum mast (it doesn't have to
> actually be the full 66 feet tall) would be stronger than buying one
> of those telescoping fiberglass poles that I see frequently
> advertised on most of the ham radio web sites. They appear to become
> pretty small at the top and can probably only support a number 18 to
> 22 wire inverted vee for a field day weekend, at best. Just a sturdy,
> tall support for a wire antenna was my real interest in considering
> this telescoping mast project. My Buternut HF6V more than performs
> well for any DX I might want to chase.
>
>
As a practical matter, fiberglass structural material (e.g. Extren) is
about the same price as aluminum, about the same strength, but twice the
flexibility. It's available in 20 foot lengths as tube, angle, square
box, I beam, etc. One online catalog had 1.25" OD x 0.125" wall x
20foot sticks of Extren 525 for $100. (525 is UV inhibited and fire
retardant.)
http://www.ryanherco.com/Auto/price.cfm?FAM=775&SEC=860&GRP=140&CAT=110
is another price list site
round 2"x1/8" wall 500 material is $2.82/ft on the ryan herco site (but
I think that might be a typo.. it's cheaper than 1.5".. or maybe it's
just a more common size... That's $60 for a 20 foot stick.
You can just drill and bolt the stuff, or you can use a suitable epoxy
to join it. I've done both.. obviously, epoxying is permanent. for this
sort of thing square tube is easier to work with than round.
That would save you the hassle of hooking 6 foot sections together.
(granted, you can get aluminum tubing in 20 foot lengths, too, just not
delivered by UPS)
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