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From: "Doug Westacott" <ve6pr@canada.com>
Sent: Sunday, September 19, 2010 6:16 PM
To: "Jim Thomson" <jim.thom@telus.net>; <towertalk@contesting.com>
Subject: RE: [TowerTalk] Free climbing a 1700' tower
>
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> Jim
>
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>
> re: para 3
>
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> A fall arrest cable or rail prevents the climber from falling about "zero"
> inches.. actual distance depends on how tight your harness is on...
## it all depends on the length of the lanyard used, and whether it is say
a 3'-6' rigid rope type, or a 3'-6' bungee type....and where you hook
to... like the hook 7" below
your neck [on the newer full fall arrest harness]. In the old 1976 Roh
catalog, they had the same thing, but it hooked to your waist belt, right
where your belt buckle would be.
If a full fall arrest body harness is used, and lanyard hooked to the 'D'
ring part way down the middle of your back, and you fell, and depending on
length of lanyard,
and where on the safety cable / rail it's sitting at the time, you could
fall anywhere from a few inchs to several feet, before it engages.
>
>
> The steel cable or rail is fitted with a slider that moves up freely but
> provides a postive dead stop brake in the event of sudden downward
> movement....
## The pro-tower installer here in town uses both systems, depending on
what commercial tower he is on. He prefers the safety rail to the 3/8"
cable.
>
>
>
> Please check either the Saliwa or Trylon sites for a complete description
> of these devices...foolproof and safe....
>
> I install these on all of the commercial towers I build (mandatory by law
> in Canada)...
## I just read on the web, where a fellow [ in eastern canada] fell 60'
before the RAIL engaged itself. The fellow was seriously injured. Forget
who made the rail, but they have been recalled.
The manufacturer [ it was not trylon] no longer makes the rail system. CSA
tested it.. and IF you fell straight down, it engages. IF you fall,
leaning forward, it will also engage.
However, if you fell leaning backwards, the mechanism would NOT engage!
Trylon sez that if a fall occurs, the entire 3/8" safety cable has to be
tossed per csa regs..and replaced. And that
includes the entire top bolting assy/mounting plate. IMO, 3/8" winch
cable, with dual nicropress crimps at the top, and huge bolt assy, is not
abt to snap any time soon.
>
>
>
> As for Ham type tin towers ( Delhi, Trylon Titan and Rohn Bx) they can be
> installed but the towers do not provide a 5000 lb anchor point as per the
> device ratings less the point at which the splice bolts attach to the
> concrete footing....
## On the rail system for the trylon titan towers, the rail is bolted to
the tower leg, abt every foot, the entire length of the tower. In that case,
the dead weight is held by the entire rail.
If a cable is used, you are correct, the entire weight is held by the top
bolt assy. Trylon titan towers are made of 32 ksi sheet metal, and are not
super strong, or thick leg material [ditto with braces]. They do not meet
CSA S-37 cdn specs either. The super titans [legs] are made from 51 ksi
steel, and braces from 46 ksi steel..and do meet S-37 specs. The legs are
very thick [up to as much as 3/8"] ..and will handle as much as 25 mm of
ice...and high winds simultaneously. However, the super titans use those
5/8" x 10" long climbing bolts, which alternate sides, every 12" ..and
they form a 60 deg angle. Fall, and ur chances of getting a bolt through
your face/eye
are very good. Eye protection is a good idea. Some debris/dirt, etc,
blows into your eye, it will drive you nuts.
>
> > All said .. fall arrest cables and rails are the industry standard
> > here... I use them every day...
## I have yet to see one cdn ham tower with either a cable or rail system
installed. I was very close to installing the rail system on my
trylon..then dumped the plan, because I was going to install
a 32" ID/ 40" OD tic-ring rotor to the tower [at the 56' level] . It
was going to be a gong show to stop below the ring, then re-start above the
ring. Side mount rotor's / fixed yagis, rotatable towers,
make implementing any kind of safety rail/cable almost impossible. On
a K0XG rotating tower, it flat out can't be done..too bad.
>
> Lastly..I usually check the slider and cable at about the 3 foot level
> prior to a climb.. a simulated fall...simply let the slider take my weight
> and then tell my ground guy I'll be back !!!
## excellent idea. Have you see how much they want for a commercial
version of either a rail or safety cable complete assy ?? Most hams
would not do it based on cost alone. However, 3/8" winch cable
and nicropress crimpS are cheap... and after seeing what a commercial assy
looks like, [ including the bottom spring/bottom turnbuckle] , I would not
hesitate to HB such an assy.
later... Jim VE7RF
>
>
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> Doug
>
> VE6PR
>
>
>
>>------- Original Message Follows -------
>>From: "Jim Thomson" <jim.thom@telus.net>
>>To: <towertalk@contesting.com>
>>Subject: [TowerTalk] Free climbing a 1700' tower
>>Date: Sun, 19 Sep 2010 05:08:25 -0700
>>
>>Date: Sat, 18 Sep 2010 13:18:22 -0500
>>From: "Ronnie Carter" <towerbob@hotmail.com>
>>Subject: [TowerTalk] Free climbing a 1700' tower
>>
>>I always free climb, then snap the belt when I get where I'm going. Been
>>doing it for 20 years or more. There's just one rule -- hold on tight.
>>But I'm 54 now, and suspect that in a few years I might start hooking up
>>all the way.
>>
>>## I have been doing the exact same thing since 1972.... climb up...then
>>hook on. All the tower's I have had, are too wide to put a lanyard
>>around [ 30" face width towers, straight sections] . The folks here in
>>town, that had guyed
>> rohn 25/45 all put the lanyard right around the tower... then un hooked,
>> and re-hooked at each guy station. [ one lanyard used] That always
>> seemed silly to me, since if u fell, you would slide all the way down the
>> side of the tower anyway.
>>
>>## I mention before, a month ago, about using the 3/8" steel safety
>>cable, fall arrest system used on all commercial towers... and the
>>consensus was/is... if you fall, you will fall as much as 6' before it
>>grabs. At which point, you will get one of the 5/8" x 10" long step
>>pegs in your eyes [ an wireless/ trylon super titan free standing towers]
>>On a guyed 25/45/55 tower, the 3/8" safety cable would work... provided
>>you had no tic-ring rotors, or swinging gates. The safety cable will also
>>not work on a rotating tower.
>>
>>## Then someone mentioned using TWO lanyards.... both with gorilla hooks
>>on the ends....and alternately clipping and un-clipping the 2 x hooks as
>>you climb up/down. I have not tried this..yet, but it's probably a good
>>idea, although awkward, and time consuming. At least if you fell, you
>>won't fall very far. On the 30" tower I had.. I just free climbed up
>>the IN-side of it, the entire length. The yagi's were all fixed on EU,
>>so no rotor plates/masts, etc. It just feels a lot safer going up the
>>inside of a tower, than the outside. On my 40' trylon, I could climb
>>the inside of it too.
>>
>>## back in 1977, I had mast steps welded to the 2" mast on a 60'
>>tower....so free climbed the 60' tower.. then free climbed the 11' mast.
>>... then wrapped the lanyard around the mast a few times, to take up the
>>slack. [ no easy trick, as your body is in the way, and u have to wrap it
>>several times]. I said I would never use mast steps again. On this new
>>crank up, there will be mast steps clamped to the 2" chromolly mast [3/8"
>>thick wall tubing]. At least with the tower nested, tower is only 24'
>>tall, then 14' of mast above it. IMO, too much hassle trying to remove a
>>prop pitch from a crank up, then lowering a mast, installing yagi's, then
>>raising again, then re-installing the PP. I have 2 x lanyards, one with
>>gorilla hooks. I should make a custom 3rd lanyard... really short, like
>>12"- 15" long for the mast.. once up there.
>>
>>## doing this stuff when you are 20 yrs old is one thing. Climbing in
>>your 50's is another. I'd agree with K7LXC.... you have any kind of med
>>emergency, get stung, get caught in a rain storm, or a sudden wind storm
>>comes up, or smash your fingers, knees, cut yourself, and you can be in
>>serious potential trbl....real fast. Meanwhile the wife is doing
>>laundry, or out shopping...... and warns you to 'be safe up there'.
>>Perhaps a cell phone would be the ticket..then at least you could call
>>911.
>>
>>later... Jim, VE7RF
>>_______________________________________________
>>
>>
>>
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>
>
>
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