[TowerTalk] Regarding Worm Gear Drive Winches

[jimlux]

Brad Pioveson W9FX wrote:
> Here's a question for the ME's.  Can a worm gear drive winch without
> a brake system safely be used on a telescoping tower - which tower
> does not have a latching mechanism to support the tower in the
> extended position?
> 

Depends on the particular worm gears (more specifically, the pitch of 
the worm).  It's like whether you can backdrive a lead screw. Sometimes 
you can, sometimes you can't.  The finer the pitch (= higher numerical 
gear ratio) the more likely you can't backdrive.


> In other words, can a worm gear drive winch be reverse driven such
> that the tower can fall in the absence of a braking mechanism?
> 
> I have a TriEx W-51 tower that came from the factory equipped with a
> worm gear drive winch.  When I received the tower, the winch handle
> was missing.  If I do not replace the handle, I can likely drive the
> tower up and down using a 1/2" low speed rt angle electric drill.
> If, however, the handle needs to be there and if said handle needs to
> be locked in place to prevent self-unspooling of the cable, then I
> had best find a handle...
>