The best is to use flanged masts and a double-worm gearbox.
I never had any problems with that configuration, even not at 200km/h:
http://www.pbase.com/df3kv/image/50045855
http://www.pbase.com/df3kv/image/50045854
http://www.pbase.com/df3kv/image/21712154/large
73
Peter
-----Original Message-----
bounces@contesting.com] On Behalf Of ve4xt@mts.net
This is all a very good argument for an Alfa-Spid style of controller: mast
slips, adjust the controller. Period. No climbing. No pinning. No stripped
gears.
(At least until the slippage is, I think, 320 degrees, at which point you
reach the upper limit of the box's ability to adjust.)
The Spid uses pulses to tell the controller the antenna's moving, so there's
no physical connection between the mast and any indicator rheostat.
> From: "Al Williams" <alwilliams@olywa.net>
> Date: 2006/03/01 Wed AM 11:53:28 CST
> To: <towertalk@contesting.com>
> Subject: Re: [TowerTalk] Rotor Stripping Gears?
>
> A cutaway drawing of the M2 2800 rotator shows five (5) regular type
gears
> between the mast clamp/mast and the worm drive!
> I have noticed that there is a fair amount of movement of the boom
caused
> by the wind apparently acting on the backlash of the five gears.
>
> The M2 specification lists a braking torque of 17000 in-lbs while also
> stating that "Precision wormdrive - cannot be reversed by mast torque;
NO
> BRAKE RQD. As mentioned by others M2 voids the warranty if the mast
is
> pinned to the rotator clamps.
>
> Question is, what does M2 really mean by their braking torque and how
was it
> determined? Also how does one determine the torque caused by the
wind load
> and inertial load of the antenna/mast assembly?
>
> Also note that there are two long elements on one side of the mast vs
only
> one long element on the other side..
>
> k7puc
>
> ----- Original Message -----
> From: "peter.voelpel" <df3kv@t-online.de>
>
> I learned it twice that worm-gear drive rotators also loose their gears.
> Two of my Prosistel PST2051 failed with a beam of 0,9m2 at 10m height
and
> only 60km/h wind gusts at that time.
> The worm axle pushed the bearing completely out of the housing which
> ruined....
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