That was our thinking here, Pete. Big rotator, big antenna,
HD mast. The rubber flex disc was just something that
my friend and I thought would be fun to try. We figured
that as long as that it didn't tend to enhance or sustain any
mechanical resonances in the system, then it could nothing
but improve reliability.
Of course experience may prove that we were wrong.
Currently the rotator is only turning about 200 degrees
out of 360. I am hoping that its just the a loose bolt keeps
the output spline shaft from dropping down into the gearbox,
but I won't know until I climb tower sometime in the next
few weeks.
73 de Mike, W4EF.....................................................
----- Original Message -----
From: "Pete Smith" <n4zr@contesting.com>
To: <towertalk@contesting.com>
Sent: Wednesday, December 19, 2001 5:14 AM
Subject: Re: [TowerTalk] Hink and Kinks
>
> At 09:14 PM 12/18/01 -0800, Mike wrote:
> >
> >Yes, the drivetrain disks work because they use staggered
> >bolt patterns each with 4 metal sleeves buried in the rubber
> >disk. This allows the bolts to be tightened down hard
> >metal to metal with no sloppy rubber in between the bolt
> >head and the mating surface.
> >
> >In order to install a rotator with rubber shock mounts between
> >the base and the mounting, a similar scheme that allowed
> >for hard mounting of the bolts metal-to-metal would be
> >required.
>
> Hi Mike et al. Yaesu apparently makes a device that does exactly what
Mike
> suggests. See this dated December 2000 from N7US:
>
> "Has anyone used one of these things [Yaesu GA-3000 tower absorber] and,
if
> so, what do you think?? They are shown on p. 141 of the Fall/Winter AES
> catalog. It looks to me to be a two-plate sandwich with big rubber
> grommets/bumpers in between. I'm assuming it mounts below a rotor to
> minimize the torque on a tower."
>
> In a reply, Mike recounted his experience with a Mercedes drivetrain disk
> as a mast absorber, which needed jam nuts added to make it hold together -
> simple lockwashers weren't sufficient over time.
>
> I guess I'm not persuaded by the idea that using any such device is just
to
> make up for marginal mechanical design. After all, the natural
environment
> provides all kinds of uncommon load events -- the 100-year flood, the
freak
> windstorm, etc. -- and making provision for such things isn't a bad idea,
> even if all normal loads are well within spec.
>
> This is not to endorse the original Hints and Kinks idea, which I never
> saw.
>
> 73, Pete N4ZR
> www.qsl.net/n4zr
>
>
>
>
>
> AN Wireless Self Supporting Towers are now available! Windloading tables,
> foundation diagrams and charts, along with full details are now at the
> AN Wireless Web site: http://www.ANWireless.com
>
> -----
> FAQ on WWW: http://www.contesting.com/FAQ/towertalk
> Submissions: towertalk@contesting.com
> Administrative requests: towertalk-REQUEST@contesting.com
> Problems: owner-towertalk@contesting.com
>
>
AN Wireless Self Supporting Towers are now available! Windloading tables,
foundation diagrams and charts, along with full details are now at the
AN Wireless Web site: http://www.ANWireless.com
-----
FAQ on WWW: http://www.contesting.com/FAQ/towertalk
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
|