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Re: [TowerTalk] Correct placement and use of Chicago Grips?

To: "'K3GM'" <k3gm_qrp@verizon.net>, <towertalk@contesting.com>
Subject: Re: [TowerTalk] Correct placement and use of Chicago Grips?
From: "Dick Green" <wc1m@msn.com>
Date: Fri, 29 Jun 2007 11:20:11 -0400
List-post: <mailto:towertalk@contesting.com>
The procedure is pretty straightforward and the parts don't interfere with
each other as much as you might think.

I use five-hole equalizer plates that are welded to the anchor rods. The
extra holes are helpful as attachment points for the come-along when you
have only three guy wires. If you have three-hole plates, you can attach the
come-along to the middle and top holes when you tension the bottom and
middle guys. Frankly, I don't know how people attach the come-along for the
top guy, but imagine that it can be attached to the rod behind the equalizer
plate without too much difficulty. If that puts the come-along at an awkward
angle with respect to the equalizer plate, then you can use a short section
of wire rope with loops at both ends made with wire rope clips. I'm sure
people who have experience with the three-hole plate will chime in here. 

For the first (lowest guy), you attach the turnbuckle to the lowest hole in
the equalizer plate and the fixed hook on the come-along to the middle hole.
For the middle guy, you attach the turnbuckle to the middle hole in the
equalizer plate and the fixed hook on the come-along to the top hole. You'll
probably need a shackle to attach the come-along hook to the equalizer
plate. The hook at the end of the come-along cable attaches to the Klein
grip. The Klein grip is slipped on the guy wire.

Note that you have to put the Klein grip far enough up the guy to ensure
that it won't bump into the come-along before you're at the target tension
(i.e., that you have enough come-along cable to do the job.) But you can't
put the Klein grip too high. Otherwise, when the guy is tensioned you'll not
be able to reach high enough to attach the Loos gauge above it and/or remove
the Klein grip when you're finished. A little practice helps.

Extend the turnbuckle so you have about an inch or two of thread left on
both screws. Tension the guy with the come-along. Use a Loos gauge to get
within a couple hundred pounds or so of final tension. If you have three
Klein grips and three come-alongs, repeat this procedure with the other two
guys. Once you have tension on all three guys, you can check the plumb on
the tower and adjust the come-alongs as necessary -- tightening here,
loosening there. I find it best to sight straight up the tower from the
bottom. In determining which guys to tighten and which to loosen, remember
that you want to end up with equal tension on all three guys. Also, you're
going to lose a little tension when you transfer each guy to the permanent
grip. 

Once the tower is plumb, and you have all three guys at the same tension and
within a couple hundred pounds of final tension, put on the guy grips. For
each guy, slip the guy grip and thimble through the hole in the turnbuckle
and wrap it onto the free end of the cable that extends below the Klein
grip. Tighten the turnbuckle until the come-along cable starts to slack.
Then you can remove the come-along and Klein grip. Keep track of the number
of turns you made to tighten the turnbuckle and make the same number of
turns on the other two guys to release the come-along. Re-check tension on
all three guys and tighten as necessary to maintain plumb and achieve the
target tension (10% of breaking strength for steel guys, 15% of breaking
strength for Phillystran guys.)

When you put the permanent grips on, don't wrap them all the way. Leave a
few inches at the end unwrapped so the grip can be easily removed in case
you run out of turnbuckle thread and need to reposition the grip (of course,
you have to use the come-along and Klein grip to do this.) You can rewrap a
grip twice before you have to use a new grip. Using the above procedure, I
didn't have to reposition any of my grips. The key is to make sure you
extend the turnbuckles nearly all the way at the start.

Make sure you cut your guy wires long enough to leave about 10' extra at the
bottom than you calculate will be needed. This will ensure that you don't
end up with a short guy, and will also provide lots of material for a safety
cable that can be threaded through the turnbuckles to keep them from moving.

Hope this helps.

73, Dick WC1M


> -----Original Message-----
> From: K3GM [mailto:k3gm_qrp@verizon.net]
> Sent: Thursday, June 28, 2007 8:08 PM
> To: towertalk@contesting.com
> Subject: [TowerTalk] Correct placement and use of Chicago Grips?
> 
> 
> Reading the Towertalk archives, it became apparent that 3 Chicago grips
> are favored during the guy tensioning and tower plumbing process.  Do
> I've got 3 Klein 1613-40 grips, and 3 come-alongs.  What I can't
> picture is how the equalization plate, the come-along, the grip, and
> the turnbuckle all go together without one interferring with the other.
> Can anyone explain?  Photos?
> 
> tnx, de K3GM

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