Carl,
I can't say for sure but others have told me that cold flow was the
primary reason it was used rather than Teflon. In aircraft usage, wires
are bundled and lashed down so creep is a big deal if the wire is lashed
to some metal part. I just took some #20ga Tefzel and some #20 ga
Teflon wire and doing a totally unscientific test I was able to mark the
Teflon wire with my fingernail much deeper than the Tefzel.
73, Larry W0QE
Carl wrote:
> Larry, is the cold flow performance of the Tefzel better than Teflon?
>
> Carl
> KM1H
>
>
>
> ----- Original Message ----- From: "Larry Benko" <xxw0qe@comcast.net>
> To: "Harold Mandel" <hmandel@barantelecom.com>
> Cc: <amps@contesting.com>; "Rich Schmuke" <rdj@wildblue.net>
> Sent: Monday, July 28, 2008 11:18 AM
> Subject: Re: [Amps] Wire
>
>
>> I had responded to Rich last week but I guess he either didn't like my
>> answer or just wanted more opinions.
>>
>> Look at
>> http://www.welchfluorocarbon.com/techdata.htm#Table1FluoropolymerSelectionGuide
>>
>>
>>
>>
>> for more than you probably want to know. I measured some 20 or 22 gauge
>> twisted Teflon and Tefzel wire a few years ago and couldn't see any
>> difference other than Tefzel has a slightly higher dielectric constant
>> (2.6 vs 2.2). Tefzel is not rated to quite as high temperature but both
>> are plenty high enough. :)
>>
>> Also in may last job we used only Tefzel wire in aircraft products. I
>> think it is becoming more common that Teflon insulated wire. Also the
>> breakdown voltage is higher than Teflon and the material is harder which
>> is good for wire that is wound against a surface. Both Teflon and
>> Tefzel are DuPont registered trademarks.
>>
>> 73, Larry W0QE
>>
>>
>> Harold Mandel wrote:
>>> Rich
>>>
>>> [snip]
>>> Does any know a reason why TefzelR ETFE insulated wire would not be as
>>> good or better because the dielectric strength is even higher...
>>> [snip]
>>>
>>> A balun will generate heat.
>>>
>>> Manufacturers of popular baluns realized
>>> stations would attempt to load RF into
>>> huge mismatches and because they wanted
>>> to reduce warranty claims, went for the
>>> cheapest solution that would withstand
>>> heated wires the longest.
>>>
>>> While PTFE insulated wire is a common
>>> choice for commercial balun products there
>>> are always upgrades in quality.
>>>
>>> Why not build such a device and test it
>>> using your ETFE stuff? Mismatch it
>>> and report on its ability to handle
>>> high temperatures.
>>>
>>> I for one would be very interested in
>>> insulation that would surpass PTFE.
>>>
>>> Hal Mandel
>>> W4HBM
>>>
>>>
>>> _______________________________________________
>>> Amps mailing list
>>> Amps@contesting.com
>>> http://lists.contesting.com/mailman/listinfo/amps
>>>
>>>
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>>
>
>
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