I have considered building a rotor shock absorber by mounting 4
conventional equipment shock absorbers between 2 plates. I am talking
about thejobs with a bolt on top and a drawn metal shell on the bottom,
secured with 4 small bolts. Some are built to handle both vertical and
horizontal forces. They have been available at near give away prices in
surplus and ham flea markets. I have seen catalogs which give the load
ratings. I haven't tried them but think it has possibilities.
73, Dan, N5AR
Pete Smith wrote:
>
> 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
>
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AN Wireless Self Supporting Towers are now available! Windloading tables,
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