A G-2800 rotor is really overkill for a TA-33….the the G-800 should be more
than enough
Sent from my iPhone
> On Apr 21, 2026, at 6:33 PM, Jim Lux <jim@luxfamily.com> wrote:
>
>
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>
>
> Thrust bearing (designed to take a load axially) or a bearing to take side
> loads (e.g. wind loads) - Especially indoors, a sheet of High Density
> Polyethylene with an appropriate sized hole will work great. A cutting board
> drilled, then sawed in half across the hole so you can fit it around the
> mast, would work well. You're looking at a very low rotation rate and an
> even lower duty cycle. HDPE is very "slippery" (almost as good as PTFE).
>
>
>
> On Tue, 21 Apr 2026 13:58:49 -0400, Dave WB2PJH via TowerTalk
> <towertalk@contesting.com> wrote:
>
> Thanks to all for the suggestions.
>
> After some investigation, it will be much less expensive to make my own
> supports from some 3/4" or 1" pipe with flanges and use some steel plate
> for the rotator plate bottom and top plate. If I lived closer to Jon I'd
> purchase a cutoff section and plates, but my current plan is to out up some
> sturdy (2x6) stringrers across the roof joists, sister them and likewise
> reinforce the base so there will be minimal pressure on the roof structure
> and distribute the weight or the ceiling joists below. I can cut and
> thread 3/4" pipe which should, given the short distance, support the
> rotator and thrust bearing. Yaesu has a handy formula and table in the
> manual and HRO sells a G-2800 motor (but not the connector) which will work
> with my RT-21 controller and a G-065 thrust bearing which should more than
> handle the TA-33 with the WARC mods. I have a 2 inch by 15 ft 6061
> aluminum mast so half will be inside and the rest outside, and a stock vent
> pipe collar should keep the water out. When it's time to move, I can
> unbolt everything and cover the hole with one of the extra shingles. If
> anyone sees a problem with this plan, feel free to correct me.
>
> If anyone has or know of anyone selling a serviceable rotator and/or thrust
> bearing at a reasonable price, I'm interested, otherwise I'll buy them new.
> I've always had good luck with Yaesu rotators, but would consider any
> heavy duty model that's not a repairman's special.
>
> 73,
> Dave WB2PJH
>
>> On Tue, Apr 21, 2026 at 1:31 PM Mickey Baker wrote:
>>
>> This seems like a waste of a tower section unless the structure of your
>> attic specifically matches structurally.
>>
>> Pressures on the mast are primarily vertical, so the bottom surface must
>> bear the static weight of the antenna, mast and rotor unless you devise
>> another rotating scheme.
>>
>> Lateral pressures on the opening are a function of the wind on the antenna
>> and mast that allow calculated wind load. This and should be calculated,
>> and a solution created that fits the space and will support the wind load
>> and weight.
>>
>> You can then should be able permit for the combined structure that will be
>> safe. You can actually design and document a decommissioning process so
>> that a potential buyer won't run away from you or your family down the road.
>>
>> Mickey N4MB
>>
>> “Ends and beginnings—there are no such things. There are only middles.”
>> Robert Frost
>>
>>
>> On Tue, Apr 21, 2026 at 11:29 AM Jon Zaimes, AA1K via TowerTalk <
>> towertalk@contesting.com> wrote:
>>
>>> Hi Dave,
>>> Back in the 1960's my best friend's dad was W3ANO in Allentown, PA. He
>>> had a mast going through the peak of the roof as you propose, with a TA33
>>> or similar trapped tribander on it. No rotor though. The mast went through
>>> the ceiling on the 2nd floor and he had fashioned a brake of some sort and
>>> a steering wheel on the bottom of the mast in the hallway next to the radio
>>> room. He would reach up to turn the steering wheel to adjust the beam
>>> heading, then lock it down!
>>> You will need a rubber boot where the mast enters the roof to keep water
>>> out.
>>> Rohn does have a couple of short top sections:
>>> https://www.3starinc.com/rohn_25g_antenna_rotor_and_bearing_accessory_shelf_r-bas25g
>>> or
>>> https://www.3starinc.com/rohn_25g_top_cap_thrust_bearing_plate_r-bpl25g
>>> Maybe a bit pricey for your purposes. Any cut-off straight section with
>>> two accessory shelves would serve the same purpose.
>>> I have a couple of used top sections with rotor plates in my stockpile if
>>> you are interested.
>>> 73/Jon
>>>
>>> Jon P. Zaimes, AA1K
>>> Tower climber for hire
>>> Felton, Delaware
>>> http://www.aa1k.us/
>>> Cell: 302-632-2353
>>>
>>> Reviews of AA1K tower work on eham website:
>>> http://www.eham.net/reviews/detail/12922
>>>
>>> Hug your favorite tower every day, and always stay connected to it.
>>>
>>>
>>> _______________________________________________
>>>
>>>
>>>
>>> _______________________________________________
>>> TowerTalk mailing list
>>> TowerTalk@contesting.com
>>> http://lists.contesting.com/mailman/listinfo/towertalk
>>>
>>
>
> --
> Dave WB2PJH
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