COME-ALONGS
All of the precautions stated by others are of course
important issues. But I own about 50 come-alongs
many of which claim to be made in the USA. The ones
I mentioned that are available at Sam's are of significantly
superior quality than any of the other inexpensive
ones that are commonly available and are certainly
adequate for typical amateur use. But they are made in
Taiwan for a US company. I have done a lot of
antenna and tower work in Taiwan and I've seen a lot of
junk tools--but these are a pretty good price/quality tradeoff.
In fact, I have done commercial tower work from the arctic
to the tropics for every level of government entity as well
as many companies, universities, and foreign governments.
I certainly would trust these for towers of Rohn 65 or less to
200 ft. On the occasions when I have done heavier towers
to heights in excess of 300 ft I have used chain drive tensioners
because they were available.
LOAD STRAPS
For a while I thought that the comments arose because of a
misunderstanding of the application. And that it was thought
that I was guying a tower with this stuff. This is just the flat
strapping for securing a load to a trailer. The type of thing used by
many truckers for heavy loads. Not sure what the yellow webbing is--
nylon or dacron or what--it doesn't say--only that the things are
assembled in the USA and the strapping is made in the USA and that
the tie downs meet DOT, CHP, CFR, and CCR regs. The steel
parts are made in Taiwan.
This stuff is rated at 10,000 lbs tensile and 3,300 lbs working
and is certainly adequate for hauling home a load of Rohn 45.
As usual, YMMV and caveat emptor. But based on my
professional experience both the come-alongs and the tie
downs are a "best buy" for typical light duty ham applications.
I have heavier winches and equipment for the really big stuff.
(No wenches in my tool box.)
Actually the only time I have had any "excitement" while
doing a tower was when a US-made Klein grip ("porkchop")
slipped (twice). First time I thought it was a fluke and the
second time it got retired to the landfill. Yes, it was the correct
groove for 1x7 EHS, but had been used a lot before I got it.
I immediately went out and purchased four new, HD ones.
Actually the story is interesting in that it does give some
measure of the strength of Rohn 55. I had put up the
first 40 ft of one of my 200 ft Rohn 55s and was putting
on the first set of Phillystran guys. This was the 5/16"
equivalent (11,000 lb tensile) and I had them tensioned
to about 1500 pounds (Philly says you can tension to
15% initially and with stretch they will relax to the typical
10%. When one of the Klein grips popped off the steel
section of the guy wire. The tower "sproinged" in the
direction of the other two guys that were at 1500 pounds.
Of course it overshot and rebounded, repeating this
oscillation a few times.
The tower was in extremely sandy soil that had been well
compacted. The concrete base was 3x3x4 ft 7-1/2 sack mix.
When I checked the base there was about 2 to 3 inches of
clearance around the entire base (all four sides). Careful
inspection revealed no bends or compromised welds--
demonstrating that the tower handled the 2-direction
static pull from the remaining guys as well as the dynamics
of flopping around a lot. Pretty impressive stuff. And
not even any little cracks on the surface of the concrete
where the legs entered. Guess that is why I use 7-1/2
sack mix! Of course if I had been ON he tower when it
happened I would have been catapulted into the next
county or slapped silly or worse by the tower. (What do
they call those little paddles with a ball attached by a long
rubber band? Get the picture??)
One other short story along these lines that will provide
some insight into what these towers can actually handle.
But "don't try this at home!" I had installed the last sections
of another of my 200 ft Rohn 55 towers but only had guys
up to the 160 ft level. The project got stalled for some
period of time so the tower had 40 ft of unguyed sections
above the last guy point. Same Phillystran guys at 1100
pounds (after they had relaxed and been tested with my
series dynamometer). The neighbor's property is about
1,000 acres and has a gas well near my property line
and one of the gas well workers used to shoot at things
with a high-powered hunting rifle.
I had a golden eagle that perched on my towers quite often
and one of the guy wires was shot and severed at the
160 ft level. Right at the top end where the eagle often
perched. So the other two guys were pulling the tower to the
side (seemed reminiscent of the St. Louis arch--but probably
wasn't quite as bad). So the last functioning set of guys
was at the 120 ft level. There was a LOT of unanswered tension
at the 160 ft level, and there was another 40 ft of tower above
that. I am sure that when the guy wire was shot there was a
pretty rapid acceleration of the entire structure above 120 ft
and yet there was no sign of any broken welds or other damage.
The gas well worker was never seen again--pretty much
suggesting that he was the perpetrator. I sure wouldn't
think that Rohn 45 would have survived this abuse but the
Rohn 55 did and has been solid for the ten years since
this happened. It now supports a 4-stack of 8 element
10M beams (48 ft 3" x 0.125" wall booms.)
This does teach one to be very careful--but none of
these problems were caused by a cheap come-along or
a bad strap.
BTW For light tower work I use Samson stable-braid
woven dacron ropes of 3/8 inch diameter. For the
big stuff I use the 1/2 diameter version of the same
thing (the kind of jobs where you use 30-40 ft of
Rohn 25 for the gin pole).
Sometimes things can be TOO heavy duty. Which is
why I prefer to use my John Deere Gator to put up
towers. It has the horse power to haul up Rohn 55
but not enough horse power to damage anything if
something gets hung up. And I prefer the Dacron ropes
over the steel cables. They have enough give to allow
you to fudge just a bit if need be. Typically the next Rohn
section is not quite low enough to sit down on the previous
one. Dacron has enough give so that I can get it to set
properly without having anything lowered by someone
on the ground. Important when I am doing both ends of
the job. I put up my 160M 4-square with no ground support,
climbing up and down the towers repeatedly for each section
of Rohn 25. I certainly don't recommend working alone
but on occasion it has been necessary.
--John W0UN
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