[TowerTalk] TX-472 and Ice

[K0DAN]

Depends on a lot of variables. It's not just the ice, but wind loading upon 
the steel + ice + coax + rotor + whatever other forces are acting on the 
tower. And of course, did the installation meet mfgr specs (how are they 
rated for wind/ice loading), what's the soil like, are the tower footings 
intact, etc., etc. The answers to these questions are often educated 
guesses.

About 7-8 years ago we had an amazing ice storm, I had over 1/2" radial ice 
on everything, and the storm hit before I could lower the tower (TriEx 
LM470). Once the ice was on we then got 30-40 MPH winds. It survived (so did 
the antennas!), but I was biting my nails the whole time. It took 3 days 
before the sun came out, and slowly it all melted and amazingly the antenna 
spring back to original shape.

Since that nail-biter, I always try to play cautious and lower "my 
investment" when inclement weather is forecast.

Last night, as the storm approached I went to lower the tower...there was 
already a thin layer of ice on everything. Started the motor and the fuse 
blew (usually indicates too big a mechanical load or water intrusion in the 
motor relay or starter caps). This summer I did major preventative 
maintenance, including replacing the motor caps/relay so I didn't think it 
was them. Replaced the fuse and motored the tower UP a little. Fuse didn't 
blow this time and then I was able to break a little of the ice free, then 
motor DOWN about 3-4 feet, then motor UP, then DOWN, etc. This eventually 
broke all the ice free (much of it fell on me) and I was able to get the 
whole structure down. Usually a full retraction takes about 6 minutes, last 
night it took 20 minutes what with all the UP/DOWN. It's amazing how strong 
a thin layer of ice is on all the cables and steel surfaces!

I was lucky...so were you!!!

Looking out the window now it looks like Siberia. I don't expect to do much 
operating the next few days!

73

Dan
K0DAN
----- Original Message ----- 
From: "Dan Bookwalter" <n8dcj at yahoo.com>
To: <TowerTalk at contesting.com>
Sent: Tuesday, February 01, 2011 7:45 AM
Subject: [TowerTalk] TX-472 and Ice


>I went out this morning to crank the tower down for the pending Ice storm , 
>the
> problem is that the top section is stuck , i got lucky i was cranking away 
> and
> looked up and saw about 10-12 feet of cable hanging out the side of the 
> tower ,
> which scared me to death , i quickly cranked it back up before the top 
> section
> broke loose , my question is with nothing on top of the tower except a 
> wire
> antenna , will the tower handle up to a 1/2 inch of ice when it is 
> extended to
> about 60-65 feet ? i don't think we are supposed to get any major wind 
> just
> sleet and ice.
>
> thoughts.....
>
> Dan N8DCJ
>
>
>
>
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