I never timed the manual time to run my HyGain HG-70HD crankup up or
down because I always do it in 'shifts' with rests (maybe sit in a chair
and work a 807 over for a few minutes), but I know it is about 520 turns
up and 520 turns down plus more because I never fully extend it, the
raised height short about 1-2 feet per section. I have the original
HyGain tower electric hoist system in two boxes (opened only to inspect)
but never found a reason to install it. The exercise of cranking is good
for me anyway.
I do exercise the winch once a month a few turns to ensure the pads are
always free (salt air and all that). I do bring the tower down in the
summer for cleanup, inspection and any needed repair (this time it will
be replace coax to the 2 M antenna, seems to have developed some
'bumps'). Beyond that it comes down only when absolutely necessary.
All of my sheave pulleys are SS and the shafts have also been replaced
with SS with SS clips on each end. All cable hardware (bolts, nuts,
washers) were changed over to SS. I use CorrosionBlock grease on all of
the shafts and good cable lube (couple of brands including Prelub 6)
carried by our local ship fleet rigger. As best I can I stay away from
anything that will rust in salt air.
Thank gosh for the tiltover fixture my local ship welding shop made for
me with the double pulley arrangement. More turns but less work to lay
everything over. They said we could hoist a tank!!
We've had some pretty strong blows, up into the low 80's a few times
over the years in the winter, but have not had any issues to date, tower
or antennas. The tower anchors the 40/80/160 fan dipole which has
around 60 deg between the wires horizontally, all ends around 30-40 feet
high. Wanted to use one of KF7P's wire antenna standoff's but
unfortunately it wouldn't dimensionally fit the HG-70HD so had one made
locally.
Oh, and the smaller cable for the upper sections is SS wire rope on the
advice of the ship rigger again. The original had stretched so thought
we'd go ahead and replace it. He showed me that it was just as good for
the use as regular wire rope cable. Still great even after 15 years when
he inspected the cables for me. The larger lower section wire rope is
the original that came with the tower and is also OK.
Now, if I lived in tornado or hurricane country I might do things 'up
and down' differently. But here it's just typically moderate winds,
sunny summer skies, great salmon and steelhead fishing and an average
rainfall (Jan-Dec) of around 70 inches. In July thru Sept we may get a
few days in the 80's but the 20 year monthly Jul thru Sept high temp
AVERAGE is a little over 60 with a warming trend.
Don W7WLL
On 7/9/2019 12:05 PM, Bob Shohet, KQ2M wrote:
Hi Rick,
Like I said, “I don’t know how long is required....”. I used a hand crank to crank up a very tall crankup tower
many years ago at KR2N – it may have been a TX472 but I don’t recall. It was an agonizingly slow process – it was
interminable. I didn’t time it. It’s just a painful memory now. ;-)
I used a round number of 1’ per second to crank up with an electric winch even
though the first section is not cranked up. I had no idea that the electric winch
really operates about 1/15 of that speed!
20 Minutes? The tower would have no chance to be cranked down in response to a
significant wind or weather risk.
Bob KQ2M
From: Richard (Rick) Karlquist
Sent: Tuesday, July 09, 2019 2:26 PM
To: Bob Shohet, KQ2M ; Wilson Lamb ; undefined
Subject: Re: [TowerTalk] Fall Zones
On 7/9/2019 7:39 AM, Bob Shohet, KQ2M wrote:
I don’t know how long is required to crank down at 89’ crank-up at full
extension but I would suspect that it is at least 90 seconds.
90 seconds????
My 106 foot crank up takes at least 20 MINUTES to crank down.
A lot of "stuff" can happen in that time.
The other issue is that towers without positive pull down
famously hang up in high winds at the worse possible time.
OTOH, reviewing the calcs, it appears that the weak point
in my tower is about 1/2 way up. I am guessing that it
would tend to fold over there and maybe not even hit the
ground at all. Just a guess.
Rick N6RK
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