Thanks for your reply.
The antenna is a hex beam at 25 lbs. The rotator and a small stub mast is no
more than 15 lbs. So I will have about 40 lbs about 16 feet from the hinge
which will require less than 100 lbs of down force. Then there is the weight
of the tower 2/3 of which is on the long end and 1/3 on the short end. The
tower weighs less than 200 lbs but lets err on the side of safety and call
it 200 lbs. That means the bottom of the tower requires another 66 lbs or a
total less than 166 lbs to start swinging the tower vertical if I don't
extend the base of the tower with a "cheater bar." Of course the force
required goes down rapidly as the tower swings up.
The added lever arm (cheater bar) will be at least 5 ft or more in length
reducing the force requirement to start the antenna swinging up to about 110
lbs or so. I can handle that. Adding a pulley and a rope would give me a
2:1 advantage and reduce the initial requirement to about 55 lbs which is
quite manageable. Or with 2 pulleys on one side and a single on the other
side (and a longer rope) and I get 4:1 (if I didn't get confused) requiring
about 28 lbs of rope tension which I should be able to manage on a bad day
with adverse winds maybe ratcheting the requirement up a bit.
Any mechanical types out there? Feel free to burst my bubble. I freely
admit my ignorance but ignorance is curable with education and experience.
The small hand winches I see would be very slow in tilting the tower up and
once it is over half way up the force required will be getting quite small.
I think a winch would be an impediment to progress and frustrating. Of
course if someone points out gross errors in my thinking in the direction of
much greater force requirements, I'll slap a winch on it.
Patrick AF5CK
-----Original Message-----
From: Larry Stowell
Sent: Thursday, August 01, 2013 2:23 PM
To: towertalk@contesting.com
Subject: Re: [TowerTalk] TowerTalk Digest, Vol 128, Issue 4
Patrick
I agree with you. I've had one up for 12 years and the set up is similar to
you idea, its an Aluma with the "Ground Post". I have had a C31XR on it a
4el Steppir and now a Tennadyne T-8. All with a homemade tilt plate.
My only comment is I think you might want think about a winch and pulley
system for the tilt over, my tower weight is less than 400# and the
antenna/rotor about 100# that 7ft is not much of a lever arm.
73 Larry K1ZW
Message: 3
Date: Thu, 1 Aug 2013 14:22:21 -0400
From: "Wilson" <infomet@embarqmail.com>
To: <towertalk@contesting.com>
Subject: [TowerTalk] Crankup Danger
Message-ID: <DFF9D2CAF6D84440B667BF626D5AF522@WilsonPC>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
Well, if the tower should telescope while you are on it, the shearing off of
fingers and the front of your feet might be considered an undesirable
possibility.
If you are on an upper section when the collapse occurs, you might get by
with just some foot damage and being thrown to the ground as the section you
are on drops into the next one down...
Your plan is much like the old EZWay towers. There's a book for the two
section 40 footer on BAMA. http://bama.edebris.com/manuals/ezway/rbs40
WL
------------------------------
Message: 4
Date: Thu, 1 Aug 2013 13:45:07 -0500
From: "Patrick Greenlee" <patrick_g@windstream.net>
To: <towertalk@contesting.com>
Subject: Re: [TowerTalk] Crankup Danger
Message-ID: <33410BA9704D44FC9A124C852B520E83@PatrickPC>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=response
Wouldn't you ordinarily lower a crank-up tower before climbing? If it were a
tilt over as well wouldn't you tilt it over instead of climbing it?
Patrick AF5CK
-----Original Message-----
From: Wilson
Sent: Thursday, August 01, 2013 1:22 PM
To: towertalk@contesting.com
Subject: [TowerTalk] Crankup Danger
Well, if the tower should telescope while you are on it, the shearing off of
fingers and the front of your feet might be considered an undesirable
possibility.
If you are on an upper section when the collapse occurs, you might get by
with just some foot damage and being thrown to the ground as the section you
are on drops into the next one down...
Your plan is much like the old EZWay towers. There's a book for the two
section 40 footer on BAMA. http://bama.edebris.com/manuals/ezway/rbs40
WL
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