Ted & Joyce Wilhelm wrote:
> Any suggestions to free a stuck beam...I have a TH7 on a 55 foot crank
> up that won't turn....Problem is I can't lower the tower with the beam
> pointing the way it is because of neighbors trees...If I cranked it down
> as far as I can would it be safe to place something like a 2 inch pipe
> through cross members to enable me to climb up to see what is
> happening......Brake is releasing but no movment...are the Cross members
> strong enough to hold it up as described if the cable gives way or am I
> looking to get my toes cut off?? anyone had this kinda problem????
> Thanks 73
> "HUH"
> Ted Wilhelm
Hi Ted,
This kind of problem is really frustrating on a crankup! Specially, since
you can't bring it down with the antenna at the present azimuth.
I think many of the comments of others are very safe and well intentioned.
Specially, if you are not an experienced climber.
The tower companies say in no uncertain terms, never climb a crank up! That
is because, if something goes wrong, somebody loses some digits. This has
happened many times and is very sad! But it keeps the lawyers gainfully
employed!
I happen to side with Steve, K7LXC. I'll climb any crankup that I have
blocked. I've climbed nearly fully extended towers, with similar problems.
The key is to NEVER place your hands and feet, or fall restraints into the
bracing far enough to lose body parts, or lanyards, if the cable lets go.
This happens to require a great deal of strength on the part of the climber
and a very good ground person to understand and follow the climbers
instructions.
The object is to get the tower down so that all sections are sitting on the
blocking, completely relieving all load from the pullup cable. I've done it
many times with timber blocking, but am most comfortable with 2" sch 40 pipe
(or equivalent, 2" box tubing is best) in each corner of the tower, at each
section. The blocking should sit on top of the horizontal bracing, across
each corner, and support the bottom of each each tower section.
If you are not comfortable, trying to do this on your own, get the bucket
truck and make the first priority, blocking the tower, before you try to
work on it.
It is silly to think you are safe in a bucket, without tower blocking. If
the cable fails, which is the premier threat of a crankup, the antenna will
fall and smack you on the noggin, while you are sitting in the bucket,
thinking you are safe.
I guess my opinion is that, it doesn't matter how one goes about dealing
with the problem, if the first, most critical threat, is dealt with by
properly blocking the tower.
Of course, try all of the other suggestions to try and get the antenna
rotated first, so you can bring it down. Then you'll still need to properly
block it, with the top section exposed, to get at the rotator!
73, Kurt
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