Why so high tech. The plastic that an ordinary milk jug is made from would
last a long time, especially if the exposed part was given a wrap or 2 of
88. Teflon is great stuff, but this is not a high speed bearing we are
talking about. And like several other, I think the wear is not from
rotational friction, but back & forth slop so using a bushing made out of
this type of stuff should wear as good as teflon.
To: <towertalk@contesting.com>
>Date: Tue, 08 Apr 2003 14:07:03 -0500
>From: Don Havlicek <n8de@thepoint.net>
>Organization: Tower Hill
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>To: Michael Tope <W4EF@dellroy.com>
>Subject: Re: [TowerTalk] Above the Thrust Bearing
>cc: Peter Sundberg <sm2cew@telia.com>
>cc: towertalk@contesting.com
>cc: mike@hatzakis.net
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>In recent weeks, 24" x 24" sheets of .025 Teflon have sold for less than
>$5 each on ebay.
>Don
>N8DE
>
>Michael Tope wrote:
>>McMaster Carr (www.mcmaster.com) has .025" x 6" x 12"
>>teflon-garolite sheets, but they are $42.00 each (ouch!!). They
>>also have .063" x 12" x 12" ultra-high molecular weight
>>polyethylene sheets (as suggested by W6RMK) for $2.94 each,
>>but the UV resistant variety is only seems to be available in 0.25"
>>thick sheets (probably not very flexible). They have a lot of
>>other materials available and a good search engine on their
>>website.
>>Seems like the metal shim stock (brass or aluminum) would be
>>an inexpensive and effective choice as well.
>>73 de Mike, W4EF.................................................
>>
>>----- Original Message -----
>>From: "Michael Hatzakis, Jr" <mikehatzakis@yahoo.com>
>>To: <n8de@thepoint.net>; "Peter Sundberg" <sm2cew@telia.com>
>>Cc: <towertalk@contesting.com>; "Michael Tope" <W4EF@dellroy.com>
>>Sent: Tuesday, April 08, 2003 10:07 AM
>>Subject: Re: [TowerTalk] Above the Thrust Bearing
>>
>>
>>>I have the same issue with my MA-550 and the collar that hold the tube.
>>Any ieas on where one can find this kind of teflon? I think it's a great
>>idea. I saw a localham do something like this and it was very effective
>>
>>>Don Havlicek <n8de@thepoint.net> wrote:Peter,
>>>In the ORIGINAL posting, the tower is Heights ALUMINUM.
>>>The 'guide tubing' at the top is SMOOTH aluminum tubing.
>>>He is NOT looking for a COLLAR, but something to keep the MAST from
>>>wearing against the COLLAR.
>>>My suggesting of Teflon sheet [PTFE] between these two still holds.
>>>Been there, DONE THAT with my Universal ALUMINUM towerS.
>>>Don
>>>N8DE
>>>
>>>Peter Sundberg wrote:
>>>
>>>> From my experience it is not the rotation of the tube that does the
>>>>grinding, it is the constant movement caused by the wind that does it.
>>Even
>>
>>>>a small gap between the two tubes will make it possible for the wind to
>>>>move things a little and after a few years the wear on the aluminium
>>tube
>>
>>>>is clearly visible.
>>>>
>>>>Furthermore, thin PTFE sheet as is not a good choice as a "bushing", it
>>>>will easily be punctured if the inside of the galvanized tube is not
>>>>extremely smooth and normally it is not since the galvanizing process
>>that
>>
>>>>makes the surface rather rough. PTFE is just too soft.
>>>>
>>>>73/Peter SM2CEW
>>>>
>>>>
>>>>
>>>>At 05:56 2003-04-08 , you wrote:
>>>>
>>>>
>>>>>A couple of stainless steel hose clamps (one placed above the pointy
>>>>>top tube and one below) and overlapping the top and bottom edges of the
>>>>>bearing sheet respectively will keep it (whatever the material
>>>>>chosen) in place.
>>>>>
>>>>>Of course, how many rotations of the antenna would it take to reduce
>>>>>the strength of the unprotected aluminum mast significantly (say to the
>>>>>90% level)? I am thinking that would be a serious rotator workout!
>>>>>
>>>>>73 de Mike, W4EF......................................
>>>>>
>>>>>----- Original Message -----
>>>>>From: "Don Havlicek"
>>>>>To: "Jim Lux"
>>>>>Cc: "(Reflector) TowerTalk"
>>>>>Sent: Monday, April 07, 2003 8:19 PM
>>>>>Subject: Re: [TowerTalk] Above the Thrust Bearing
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>>Jim,
>>>>>>He wants something to fit INSIDE that collar.
>>>>>>UHMW sheet isn't flexible enough for that task.
>>>>>>The Teflon sheet [about 3-4 mil] will be perfect for his task, and
>>>>>>require NO machining.
>>>>>>Don
>>>>>>N8DE
>>>>>>
>>>>>>Jim Lux wrote:
>>>>>>
>>>>>>
>>>>>>>Don't bother with Teflon... use High density (UHMW) polyethylene
>>cutting
>>
>>>>>>>boards... Less than $10 at your local discount store.. Very good
>>>>>dielectric
>>>>>
>>>>>
>>>>>>>properties, easy to cut (make sure that saw is SHARP), and almost as
>>low
>>
>>>>>a
>>>>>
>>>>>
>>>>>>>friction coefficient as PTFE.
>>>>>>>Unless you were planning to heat your antenna up hot enough where the
>>PE
>>
>>>>>>>starts to flow....?
>>>>>>>
>>>>>>>----- Original Message -----
>>>>>>>From: "Don Havlicek"
>>>>>>>To: "Jerry K3BZ"
>>>>>>>Cc: "(Reflector) TowerTalk"
>>>>>>>Sent: Monday, April 07, 2003 6:17 PM
>>>>>>>Subject: Re: [TowerTalk] Above the Thrust Bearing
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>>Jerry,
>>>>>>>>Get some Teflon sheet and cut a piece to fit. Should last a lifetime.
>>>>>>>>Don
>>>>>>>>N8DE
>>>>>>>>
>>>>>>>>Jerry K3BZ wrote:
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>>I've received several good comments and ideas, thanks. What I'm
>>really
>>
>>>>>>>>>concerned about is the aluminum mast and the aluminum tower sleeve
>>>>>>>wearing
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>>>away slowly from metal-to-metal contact. But grease isn't the only
>>way
>>
>>>>>>>to
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>>>keep them from actually touching. What about some sort of "bushing"
>>to
>>
>>>>>>>fit
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>>>between the mast and the sleeve?
>>>>>>>>>
>>>>>>>>>I was thinking of a section of thin-wall pvc of appropriate diameter
>>>>>and
>>>>>
>>>>>
>>>>>>>>>wall thickness, sliced length-wise and inserted betwen the mast and
>>>>>>>sleeve
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>>>on opposite sides of the mast, then clamped to the mast above and
>>below
>>
>>>>>>>the
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>>>sleeve. The idea would be for the pvc to be sacrificed and replaced
>>>>>>>every
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>>>few years as necessary. I'm no engineer and I don't even play one on
>>>>>TV,
>>>>>
>>>>>
>>>>>>>so
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>>>any comments from those more talented than I?
>>>>>>>>>Jerry K3BZ
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>_______________________________________________
>>>>>>>>>
>>>>>>>>>See: http://www.mscomputer.com for "Self Supporting Towers",
>>"Wireless
>>
>>>>>>>Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
>>>>>any
>>>>>
>>>>>
>>>>>>>questions and ask for Sherman, W2FLA.
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>>>_______________________________________________
>>>>>>>>>TowerTalk mailing list
>>>>>>>>>TowerTalk@contesting.com
>>>>>>>>>http://lists.contesting.com/mailman/listinfo/towertalk
>>>>>>>>
>>>>>>>>
>>>>>>>>_______________________________________________
>>>>>>>>
>>>>>>>>See: http://www.mscomputer.com for "Self Supporting Towers",
>>"Wireless
>>
>>>>>>>Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
>>>>>any
>>>>>
>>>>>
>>>>>>>questions and ask for Sherman, W2FLA.
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>>_______________________________________________
>>>>>>>>TowerTalk mailing list
>>>>>>>>TowerTalk@contesting.com
>>>>>>>>http://lists.contesting.com/mailman/listinfo/towertalk
>>>>>>>
>>>>>>>
>>>>>>_______________________________________________
>>>>>>
>>>>>>See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
>>>>>
>>>>>Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
>>any
>>
>>>>>questions and ask for Sherman, W2FLA.
>>>>>
>>>>>
>>>>>>_______________________________________________
>>>>>>TowerTalk mailing list
>>>>>>TowerTalk@contesting.com
>>>>>>http://lists.contesting.com/mailman/listinfo/towertalk
>>>>>
>>>>>
>>>>>
>>>>>_______________________________________________
>>>>>
>>>>>See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
>>>>
>>>>Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
>>any
>>
>>>>questions and ask for Sherman, W2FLA.
>>>>
>>>>
>>>>>_______________________________________________
>>>>>TowerTalk mailing list
>>>>>TowerTalk@contesting.com
>>>>>http://lists.contesting.com/mailman/listinfo/towertalk
>>>>
>>>>
>>>>_______________________________________________
>>>>
>>>>See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
>>Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
>>questions and ask for Sherman, W2FLA.
>>
>>>>_______________________________________________
>>>>TowerTalk mailing list
>>>>TowerTalk@contesting.com
>>>>http://lists.contesting.com/mailman/listinfo/towertalk
>>>
>>>
>>>_______________________________________________
>>>
>>>See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
>>Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
>>questions and ask for Sherman, W2FLA.
>>
>>>_______________________________________________
>>>TowerTalk mailing list
>>>TowerTalk@contesting.com
>>>http://lists.contesting.com/mailman/listinfo/towertalk
>>>
>>>Michael Hatzakis, Jr MD
>>>Physiatrist, Treating Individuals with Neuromuscular Disabilities
>>>Consultant, Information Technology Based Health Care Solutions
>>>
>>>
>>>---------------------------------
>>>Do you Yahoo!?
>>>Yahoo! News - Today's headlines
>>>_______________________________________________
>>>
>>>See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
>>Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
>>questions and ask for Sherman, W2FLA.
>>
>>>_______________________________________________
>>>TowerTalk mailing list
>>>TowerTalk@contesting.com
>>>http://lists.contesting.com/mailman/listinfo/towertalk
>>
>>
>
>
>_______________________________________________
>
>See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
>Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
>any questions and ask for Sherman, W2FLA.
>
>_______________________________________________
>TowerTalk mailing list
>TowerTalk@contesting.com
>http://lists.contesting.com/mailman/listinfo/towertalk
Jim Rhodes K0XU
jim@rhodesend.net
|