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Re: [TowerTalk] Tower winch failure

To: "towertalk reflector" <>
Subject: Re: [TowerTalk] Tower winch failure
From: "Al Williams" <>
Date: Mon, 19 Mar 2007 09:41:34 -0700
List-post: <>
Are you referring to the winch being used to tilt the tower over or to raise 
the tower when it is in vertical position?  If the latter then the winch 
cable is always loading the winch and would not operate in free wheel as 
mine does when tilting the tower up or down.

This morning I went to both of my towers (one is horizontal now and the 
other is vertical).  I observed the pawl and pawl gear.  As Alan mentions, 
the pawl gear rotates and pawl bobs in and out as the winch cable  is being 
wound in but does not when the winch cable is being let out.  I did not see 
any lateral (along the axis) movement of the pawl gear. I surmise that the 
purpose of the spring is to bring the pawl back out as the pawl gear rotates 
between teeth.

After cranking the winch to make the cable taut and then reversing to play 
out the cable, the braking mechanism is operating which requires force on 
the handle to overcome the braking.  As the cable becomes less taught the 
braking mechanism applies less and less force and shortly gravity on the 
winch handle is enough to overcome any residual braking that is still in 
operation.  As mentioned the pawl gear and pawl is not operating during the 
cable let out.

I will appreciate if anyone can explain how the braking mechanism actually 
works to decrease the braking pressure on the pads when the load on the 
winch is decreased?

I write these lengthy postings to alert readers that the Fulton k1550 and 
k2550 definitely can get into a free wheeling mode without a winch failure. 
It appears that if one goes from a taut (loaded) winch directly to let out 
the cable the winch braking mechanism will hold the tower without the handle 
being held.  However if the winch cable is slack (unloaded) and the tower is 
moved to begin its lowering (tilt) the braking mechanism will not be 
operating and the tower can crash to the ground.

When preparing to tilt the tower back down, be sure to crank the winch until 
the cable is taut.  Then when pulling on the handle to let out the cable to 
lower the tower be sure to notice that it requires considerable force on the 
winch handle to move it.  Then it is safe (probably)  to move the tower into 
a falling position.


----- Original Message ----- 
From: "Alan NV8A" <>
To: "towertalk reflector" <>
Cc: "Al Williams" <>
Sent: Monday, March 19, 2007 7:49 AM
Subject: Re: [TowerTalk] Tower winch failure

> When I examined the winch on my HDX-555, it seemed that the brake 
> mechanism applied permanent friction between the shaft and the toothed 
> wheel, but when the cable was being wound in the pawl allowed that toothed 
> wheel to turn freely. When the cable was being let out, the spring-loaded 
> pawl prevented the toothed wheel from turning, the friction being 
> sufficient to prevent free-wheeling and in fact requiring considerable 
> effort let the cable out and lower the tower.
> AFAICS, the only way it can free-wheel is if something moves out of 
> alignment or if the pawl fails to engage the toothed wheel due to spring 
> failure or lack of lubrication of the pivot.


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