I was fortunate to have a 12" dia X 10 " tall Teflon solid ROD machined to
fit the Rohn AG45 top plate hole 8 inched inserted snugly in the hole with a
2" tall collar. An 11" in dia. 1/4 thick SS plate with a 8 " tall 2.375 OD
2.065 in SS DOM tube welded over the center hole a mast stabilizer
with three 3/8 " SS locking nuts welded 120 deg. apart.
This is now on my 15 meter Tower and top beam was on another tower with a 3
element 40 meter beam. a thin film of Mobil 1 WOW
Smooth rotation .
I know this would be big $$$ to reproduce, I was lucky my Father worked at a
facility that fabricated and rebuilt Cryogenics line of liquid helium
transport/storage containers
Wayne W3EA
________________________________
From: TowerTalk <towertalk-bounces@contesting.com> on behalf of
charlie@thegallos.com <charlie@thegallos.com>
Sent: Friday, December 9, 2016 11:19 AM
To: jimlux
Cc: towertalk@contesting.com
Subject: Re: [TowerTalk] Which Thrust Bearing to Use
<snip>
>
> Torlon is a bit pricey... $1200 for a 12x12 sheet 1/2" thick
>
> Moly filled Nylon is $37 for a 1" thick piece 6x6" - Says it can be
> used outdoors, It's black, but that doesn't always mean it's UV resistant.
>
> Black acetal (Delrin) is $26 for the same 1"x6"x6"
<snip>
Which is why I said we don't need torlon of vespil <g>
Usually, if you are using those, you get them injection molded to shape,
unless it is a high buck one off, as they material is really priced per
oz, so as you would be removing the whole middle. If you were in mold it,
there is much less there - but that is talking production, making molds
etc, unless you can find one of the plastics houses that offers a hat
bearing say in 2.25" ID
Done right, as the hat shaped bearing is UNDER metal, and never exposed to
UV, it'll never be an issue. You can also use the Delrin, or even filled
delrin
Like I said, one of those applications where the fact we are using ball
bearings is just old fashioned, and today not even close to best practice.
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