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[TowerTalk] Disassembling Rohn 25 foldover help

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Subject: [TowerTalk] Disassembling Rohn 25 foldover help
From: (Stan Griffiths)
Date: Sat, 28 Jun 1997 00:48:54 -0700 (PDT)
>I'm assuming that I will run into some sections that won't come apart
>easily on this 15 year old tower.  I plan to spray all bolts/joints with
>penetrating oil about 3 days before disassembly time and again a day

Good idea.

  I would like some comments on the use of a propane torch to heat
>the 'stuck' joints.  With most metal components, I've found that a
>combination of heat and lubricants will generally do the trick.  Outside of
>damaging any paint, will a propane torch do any damage to the galvanized
>coating and/or general strength of the steel at the coupling point?

I have taken down lots of 25G but never needed a propane torch to do it.  I
don't recommend it.

  I can
>also take up a small scissors jack, but the crossmembers on #25 are so
>thin, I'm concerned about warping or breaking the welds if a jack is used.

I have used a modified scissors jack.  Modified by welding some small
lengths of angle iron to the top and bottom plates of the jack so you can
get under two horizontal braces at one time.  I also added a short permanet
handle so I can easily crank it with my hand.  I also added a safety chain
with a clip so I can attach the jack to the tower.  When the tower section
finally pops off there, you will have too many things to try to control at
once so the jack should be attached to the tower.

In using a jack, technique is everything.  You snug the jack up under the
horzontal braces and then reach up about 2 or 3 feet on the tower section
and rock it back and forth an inch or two.  The section should work itself
up a little with this motion.  Hand tighten the jack again and rock some
more.  It shoud come right off.
>Assuming I can get things off down to the hinge section, is it feasable to
>bolt the hinge together (Rohn literature refers to a 'shipping tab' of some
>sort used for this purpose), and then lower the entire boom assembly with
>the gin pole?  

I think this is too much for a standard Rohn gin pole.  I have never taken a
tilt over down so I don't really know quite what to tell you.  Take it down
in pieces if you can.  If you can't, using a block and tackle with some
mechanical advantage will take some of the strain off the gin pole.  A three
to one mechanical advantage will help a lot.

>I don't think I'll have any assistats climbing up with me.  Hopefully the
>40lb 25G sections will be manageable, but I'm not sure about that boom

Much better with a block and tackle and 3:1 mechanical advantage.

>About the guying.. Rohn seems less than their usual conservative opinions
>when it comes to guy specifications.  4ft by 6in screw anchors?  (Although
>I am told by a local installer that with our soil, these things will hold
>well beyond their 2500 lb ratings).  And even for a heavier/taller #45
>foldover, the guy placement recommended is only 30 ft from the tower base? 
>Granted, this is a four guy arrangement rather than the usual 3, but
>still..  I'm tending towards a traditional anchor/equalizer plate using a
>3x3x1' concrete block.  Or do the screw-in anchors work?  I'd also prefer
>to get the anchors out at least 40' from the tower base, unless the 4 vs 3
>guys at hinge and apex really gives enough advantage to get by with the
>smaller footprint.

I'd get them out even further.  You never know when you will want to discard
the tilt over feature and turn it into a 90 footer . . . Also, I'd get some
big anchors from the local utility supply place.

>Final question.. can somebody forward an address or telephone number for
>WB0W (the gin pole man).  $495 for the Rohn EF2545 gave me a bit of sticker
>shock.  And as an FYI, Rohn no longer supplies adapters for #55 (I plan a
>55 installation next spring), and may cease production on the EF2545 soon. 
>Apparently there is a liability factor that is scaring off most of the
>ginpole manufacturers.  

K7PN has been known to make some pretty nice gin poles.  He is a
professional welder and tower climber:  Paul Nyland, Custom Metalwork, P.O.
Box 371, Welches, OR 97067   Phone: (503) 622-4403   I don't know how much
they cost.

Good luck.


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