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
>
>
>
>
>
|