|
Matronics Email Lists Web Forum Interface to the Matronics Email Lists
|
View previous topic :: View next topic |
Author |
Message |
Ceengland
Joined: 11 Oct 2020 Posts: 391 Location: MS
|
Posted: Wed Mar 10, 2021 9:25 am Post subject: Milspec wire followup: PTFE vs ETFE |
|
|
Question for Bob N. or others who've used a lot of milspec wire:
I'm aware of the obvious differences between PTFE & ETFE; 'P' has higher temp rating but tends to 'cold flow'. I
I'm pretty sure I've encountered PTFE in pre-built harnesses from some avionics mfgrs, based on the way the insulation strips, vs known-ETFE wire I have on hand. If we install with reasonable care, is there any reason to fear using PTFE for wiring throughout the airframe?
Thanks,
Charlie
| - The Matronics AeroElectric-List Email Forum - | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
_________________ Charlie |
|
Back to top |
|
|
nuckolls.bob(at)aeroelect Guest
|
Posted: Thu Mar 11, 2021 8:37 am Post subject: Milspec wire followup: PTFE vs ETFE |
|
|
At 11:22 AM 3/10/2021, you wrote:
Quote: | Question for Bob N. or others who've used a lot of milspec wire:
I'm aware of the obvious differences between PTFE & ETFE; 'P' has higher temp rating but tends to 'cold flow'. I
I'm pretty sure I've encountered PTFE in pre-built harnesses from some avionics mfgrs, based on the way the insulation strips, vs known-ETFE wire I have on hand. If we install with reasonable care, is there any reason to fear using PTFE for wiring throughout the airframe? |
PTFE (Teflon) is not 'more' desirable than ETFE (Tefzel) and
it has some downsides.
Greg Richter and I had some lengthy discussions on this
about 17 years back after I reviewed his "Wiring for Smart People"
publication.
https://tinyurl.com/qxvr6nx
I'm aware of no manufacturer that uses Teflon
for general airframe wiring. Of perhaps 30000
feet of wire I have in inventory, I don't think
there is a hundred feet of Teflon.
Here's a copy of the Wire Bible which was
updated on the website this morning. This is
a searchable pdf file that will allow you to
quickly identify about any wire product by
specification.
https://tinyurl.com/ydgacclw
Having said that, Teflon is not 'evil'. If you
got a heck of a deal on some I would not discourage
it's use in avionics harnesses but it's kinda
finicky to strip.
https://tinyurl.com/bol9x2n
Bob . . .
Un impeachable logic: George Carlin asked, "If black boxes
survive crashes, why don't they make the whole airplane
out of that stuff?"
| - The Matronics AeroElectric-List Email Forum - | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
|
|
Back to top |
|
|
Ceengland
Joined: 11 Oct 2020 Posts: 391 Location: MS
|
Posted: Thu Mar 11, 2021 9:36 am Post subject: Milspec wire followup: PTFE vs ETFE |
|
|
On Thu, Mar 11, 2021 at 10:48 AM Robert L. Nuckolls, III <nuckolls.bob(at)aeroelectric.com (nuckolls.bob(at)aeroelectric.com)> wrote:
Quote: | At 11:22 AM 3/10/2021, you wrote:
Quote: | Question for Bob N. or others who've used a lot of milspec wire:
I'm aware of the obvious differences between PTFE & ETFE; 'P' has higher temp rating but tends to 'cold flow'. I
I'm pretty sure I've encountered PTFE in pre-built harnesses from some avionics mfgrs, based on the way the insulation strips, vs known-ETFE wire I have on hand. If we install with reasonable care, is there any reason to fear using PTFE for wiring throughout the airframe? |
  PTFE (Teflon) is not 'more' desirable than ETFE (Tefzel) and
  it has some downsides.
  Greg Richter and I had some lengthy discussions on this
  about 17 years back after I reviewed his "Wiring for Smart People"
  publication.
https://tinyurl.com/qxvr6nx
  I'm aware of no manufacturer that uses Teflon
  for general airframe wiring. Of perhaps 30000
  feet of wire I have in inventory, I don't think
  there is a hundred feet of Teflon.
  Here's a copy of the Wire Bible which was
  updated on the website this morning. This is
  a searchable pdf file that will allow you to
  quickly identify about any wire product by
  specification.
https://tinyurl.com/ydgacclw
  Having said that, Teflon is not 'evil'. If you
  got a heck of a deal on some I would not discourage
  it's use in avionics harnesses but it's kinda
  finicky to strip.
https://tinyurl.com/bol9x2n
 Bob . . .
| I'd agree that P is less desirable than E, because I'm not concerned about extreme temp ratings and had minor concern about cold flow. I had spotted a 'deal' on about 1K ft of P (IIRC, it was ID'd as M22759/9), but then found the same quantity of E (M22759/16) for about a penny more per foot. Not a big enough price delta for the hassle.Â
Many thanks for the info; if I run across some P with a bigger price delta in the future, I may well add some to my 'inventory'.
Charlie
| - The Matronics AeroElectric-List Email Forum - | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
_________________ Charlie |
|
Back to top |
|
|
bobkuc(at)gmail.com Guest
|
Posted: Fri Mar 12, 2021 7:39 pm Post subject: Milspec wire followup: PTFE vs ETFE |
|
|
I was building a plastic plane. At sun-n-fun I while back ago, I bought wire from aren't vendor. It was labeled 20-3 uninsulated and was bundle in 100 ft rolls. Now I am building an rv7a and have some left over. Is there a way to tell if the wire I have is ok for use in airplane? Coating on wire is smooth and shiny and wire looks to be coated. Should I run.p and get fresh wire from spruce?
Thanks
Another Bob K.
On Thu, Mar 11, 2021, 11:59 PM Charlie England <ceengland7(at)gmail.com (ceengland7(at)gmail.com)> wrote:
Quote: |
On Thu, Mar 11, 2021 at 10:48 AM Robert L. Nuckolls, III <nuckolls.bob(at)aeroelectric.com (nuckolls.bob(at)aeroelectric.com)> wrote:
Quote: | At 11:22 AM 3/10/2021, you wrote:
Quote: | Question for Bob N. or others who've used a lot of milspec wire:
I'm aware of the obvious differences between PTFE & ETFE; 'P' has higher temp rating but tends to 'cold flow'. I
I'm pretty sure I've encountered PTFE in pre-built harnesses from some avionics mfgrs, based on the way the insulation strips, vs known-ETFE wire I have on hand. If we install with reasonable care, is there any reason to fear using PTFE for wiring throughout the airframe? |
  PTFE (Teflon) is not 'more' desirable than ETFE (Tefzel) and
  it has some downsides.
  Greg Richter and I had some lengthy discussions on this
  about 17 years back after I reviewed his "Wiring for Smart People"
  publication.
https://tinyurl.com/qxvr6nx
  I'm aware of no manufacturer that uses Teflon
  for general airframe wiring. Of perhaps 30000
  feet of wire I have in inventory, I don't think
  there is a hundred feet of Teflon.
  Here's a copy of the Wire Bible which was
  updated on the website this morning. This is
  a searchable pdf file that will allow you to
  quickly identify about any wire product by
  specification.
https://tinyurl.com/ydgacclw
  Having said that, Teflon is not 'evil'. If you
  got a heck of a deal on some I would not discourage
  it's use in avionics harnesses but it's kinda
  finicky to strip.
https://tinyurl.com/bol9x2n
 Bob . . .
| I'd agree that P is less desirable than E, because I'm not concerned about extreme temp ratings and had minor concern about cold flow. I had spotted a 'deal' on about 1K ft of P (IIRC, it was ID'd as M22759/9), but then found the same quantity of E (M22759/16) for about a penny more per foot. Not a big enough price delta for the hassle.Â
Many thanks for the info; if I run across some P with a bigger price delta in the future, I may well add some to my 'inventory'.
Charlie
|
| - The Matronics AeroElectric-List Email Forum - | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
|
|
Back to top |
|
|
|
|
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum You cannot attach files in this forum You can download files in this forum
|
Powered by phpBB © 2001, 2005 phpBB Group
|