[TowerTalk] Your experience with rope capstan hoists or winches

[Steve Maki]

Grant,

I can only say that if the sudden load movements and other undesirable 
occurrences you describe were common happenings in the tower industry 
using industry standard catheads, they would not be industry standard 
equipment.

The AB Chance catheads in particular were designed for the overhead line 
industry, and have been used safely for decades for installing pole 
transformers and HV lines.

I wonder what type of capstan you were using while sailing. It doesn't 
sound like the right gear for tower work.

-Steve K8LX

On 9/13/2017 12:28 PM, Grant Saviers wrote:

> Years of sailing with winches large enough to pull 2+ tons taught me a 
> few lessons about self tailing and hand tailing.  Fortunately my or 
> others screw ups resulted only in flailing sails, not the disaster that 
> can happen with heavy vertical lifting.  Although an out of control boom 
> can be a lethal device as a friend was killed by one.
> 
> I would never use a self tailing winch for overhead lifting.  While the 
> grip systems usually work, "usually" is not safe enough.  They are also 
> sensitive to the size, type of line and its condition. Then the release 
> from the self tailing mechanism requires actions which often cause a 
> jump in the load part of the line.  The person releasing the line is in 
> an awkward position to control the line and has fingers close to the drum.
> 
> The person doing hand tailing needs to be thoughtful, alert, 
> communicative, physically capable, and trained.  Just as any other 
> ground crew member.  The functional problems I encountered with sailing 
> winches were overruns, jams, and run-offs.   An overrun is when a line 
> gets under a turn nearer to the load (basically a half hitch knot). 
> These can be very hard to safely or slightly release.   A jam can happen 
> when the turns get so tight together (or too many turns on the drum) 
> they need hand massaging or a turn unwound  to release and slip. 
> Run-offs are when loops slip off the open end of the capstan and the 
> tailing load jumps or becomes the total load.   These are sometimes 
> caused by the line handler not paying attention to the angle of the free 
> line to the capstan, or jumps in the load.
> 
> Is a spool drum winch better? - it depends.  Different kinds of jams 
> occur for winches of the type used on vehicles and tractors (experience 
> with this), which btw are not overhead load rated.  A crane winch spools 
> wire rope with perfect lays to not have those problems.  Like my 
> HDX589's feeder to the spool.  However, working with wire rope has a lot 
> of downsides for handling and rigging.  Not the way to go IMO for 
> amateur radio sized towers and loads especially with the rope technology 
> now available.
> 
> The pro team that did my big tower used ropes and a capstan with power 
> up/down.  That capability with a good operator avoids the problems 
> mentioned with lines on capstans.  The loads were up to 350# antennas 
> and controllable in less than a inch up/down.  A convenient tie off on a 
> cleat was on the winch mount and that was backed by a safety tie off. 
> The tower sections weighed up to 1000# and went up with a crane. 
> Although they had the gin pole and winch capacity for them the crane was 
> faster, cheaper, and safer.  For more than 25G towers and bigger than 
> tribanders, I think these are the ways to go.
> 
> Grant KZ1W
> 
> On 9/12/2017 19:23 PM, Richard (Rick) Karlquist wrote:
>> I have been reading about how nice capstan winches are,
>> but I have no experience with them.  They seem very
>> dangerous since the line comes loose and the load
>> falls down in case the line handler's attention wanders
>> for a second. It seems especially dangerous to be
>> lowering a heavy load when the handler has to pay
>> out the line just fast enough, but not too fast.
>> A foot switch is suggested, but it doesn't work as
>> a dead man safety.  The winch stops but the line
>> still slips if not held back.
>>
>> Seems like an accident waiting to happen, like free
>> climbing a tower.  Can someone with experience explain
>> how these capstans could possibly be safe?