So Chris....is the Spiderbeam mast for sale?? I'm looking for something to
use to build an 80M vertical......
73,
-Gary K9GS
GMDXA Web Site: www.gmdxa.org
----- Original Message -----
From: "EZ Rhino" <ezrhino@fastmovers.biz>
To: <w1nk@cox.net>
Cc: <towertalk@contesting.com>
Sent: Saturday, May 29, 2010 12:05 AM
Subject: Re: [TowerTalk] TA32M & Spiderbeam Push Up Mast
> Hi Frank,
>
> It seems like a feasible plan. I have a little bit of experience with the
> SpiderMast, so I can offer some insights.
>
> It is a well built unit, and quite solid when raised. Its big advantage
> is the portability. It fits inside an 8" square box about 4' long. It's
> big downfall is the major PITA to get an antenna raised on it. (It's also
> not particularly cheap).
>
> I have set up a 5 band SpiderBeam on a 50' Spidermast at Field Day and
> 7QP. The reason it is hard to erect is the increasing weight when pushing
> each section of mast up. At first it isn't that bad, but it becomes
> increasingly heavier the taller it gets. It becomes impossible (unless
> you are Mr. T or Arnold the Governator) to hold with one hand while
> tightening the clamps with the other to keep the section just raised in
> place. It really requires two people. Also, the mast when fully
> collapsed is 5-ish to 6 feet tall, which means you need to stand on a
> ladder placed right next to it in order to be tall enough to raise each
> section. This puts you at an awkward angle leaning over to muscle each
> section up. Another difficulty is when you push up a section, the entire
> mast wants to raise (or come off the ground) because of the close
> tolerances (friction) from tube to tube. Finally, the three guys need to
> be continually slackened as the mast goes taller. This is really tri
> cky if it is windy.
>
> My buddy devised a clever system of using a farm jack (hi lift jack) to
> jack up each section, making the raising somewhat easier, but creates a
> new set of problems that I won't go into here. So it takes a minimum of
> 45 minutes to get it airborn, and then you run an SWR check and realize
> the antenna needs tuning and then you let it down and start all over.
> hihi. One advantage is you can get it completely down in a couple
> minutes.
>
> We threw in the towel after 7QP this year and pulled the trigger on a
> Universal aluminum tower, 4 sections, 40' tall. With a mast it will be
> between 45-50 ft. Each tower section is tapered and nests inside the
> largest section, making transporting it fairly easy in a pickup truck. (4
> sections weigh 85 pounds). Currently I'm getting it ready for Field Day.
> I'm building a hinged base out of 2x6's and it will be guyed (obviously)
> at the top. The mast will have a hinge on the top which will allow the
> antenna placed on it horizontal to the ground when the tower is laying
> flat, then can be brought to horizontal when the tower is stood up. We're
> going to use a modified falling derrick method of raising it.
>
> Chris
> KF7P
>
>
>
>
>
>
> On May 28, 2010, at 12:57 , <w1nk@cox.net> wrote:
>
> Can anyone find anything wrong with my plans?
>
> I would love to put up my (stored) TA32M but would prefer avoiding the
> expense, etc of a tower. I happen to be looking over the Spiderbeam
> website and came across their aluminum push up mast ("heavy duty"). The
> mast is 7 sections ranging from 2.75" at the bottom to 1.5" at the top.
> Wall thickness is 2mm.
>
> According to the manufacturer this mast will support the heavy duty
> Spiderbeam which has the following specs:
> Boom: 33 ft
> Turning Radius: 16 ft
> Wind Load: 3.8 sq-ft
> Weight: 23lbs.
>
> According to the Mosley website, the TA32's specs are nearly identical.
>
> The setup would be guyed (obviously) using 2 ft ground stakes
> (Spiderbeam's) or 4 ft ground screws (DxEngineering). The rotor would be
> a base mounted HD73 (also in storage and refurbished about 15 years ago).
>
> So, tell me my thinking is too good to be true. Or for that matter if I
> have a workable setup.
>
> Frank, W1NK
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