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Re: [TowerTalk] lowering a lighting tower

Subject: Re: [TowerTalk] lowering a lighting tower
From: Ian White GM3SEK <>
Reply-to: Ian White GM3SEK <>
Date: Thu, 1 Oct 2009 16:01:44 +0100
List-post: <">>
jimlux wrote:
>Tom Rowan wrote:
>> Hello I have an alleged accident where a guy says he was lowering a lighting
>> tower with a K1550 fulton winch, when the handle spun out of control and the
>> mast crashed down. I understand the mast is held by friction disks as it is
>> being lowered. Does anyone know how this could have happened?
>Those friction clutch/brake winches do have that failure mode.  If they
>are cranked too fast or overloaded, the little brake pads get hot and
>"fade" (just like car drum brakes), once it starts to slip, it runs
>away.  In some kinds (I don't know about this one specifically) the
>brake is designed (like drum brakes) so that it brakes more in one
>direction (down) than the other (up).  for these, it is possible to
>install it backwards, as I recall (to accommodate situations where you
>want the braking when spooling IN as opposed to spooling out
>Now, whether such an event can occur on a winch operated within specs
>(load, speed) and which is well maintained?  The only cases where I've
>seen this kind of thing occur have been where there was a significant
>overload or there was some other factor (water being splashed around).
>The electric winches/hoists from Grainger/Harbor Freight have the same
>sort of scheme inside.

Another question to ask is: "Has anyone greased that winch?"

Those fiber pads sure do look dry...


73 from Ian GM3SEK

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