Matronics Email Lists :: View topic

Matronics Email Lists
Web Forum Interface to the Matronics Email Lists

Get Email Distribution Too! FAQ Search Memberlist Usergroups Register

Profile Log in to check your private messages Log in

Wire

Matronics Email Lists Forum Index -> AeroElectric-List

View previous topic :: View next topic

Author Message

mgdurand(at)yahoo.com
Guest

Posted: Thu Oct 04, 2007 8:57 am Post subject: Wire

 	  Quote: 	
		  [b]========         Allow me to suggest that M22759 Tefzel from the popular         suppliers to the OBAM aircraft industry is the finest         wire we've used in GA aircraft to date, is widely available         and reasonably priced. Praying over the Concise Dictionary         for Wire is probably not a good use of your time beyond         expanding your intellectual horizons on the universe of         wire types.               Bob . . .[/b] 	
========



Is that the stuff that is  "Flammable producing copious             amount of Dense toxic smoke (96%+ density) when it             burns rendering it virtually impossible for flight crew             to see their flight instruments." ?



Not that I would be able to afford/obtain anything better, but I'm guessing now that's why my flight instructor told me that if I have an electrical fire in-air. that  I have a poor chance of making it to the ground.



Michael

RV-7a panel building with tefzel

 [quote][b]

nuckolls.bob(at)cox.net
Guest

Posted: Thu Oct 04, 2007 10:40 am Post subject: Wire

At 09:54 AM 10/4/2007 -0700, you wrote:

 	  Quote: 	
		  ========



          Allow me to suggest that M22759 Tefzel from the popular

          suppliers to the OBAM aircraft industry is the finest

          wire we've used in GA aircraft to date, is widely available

          and reasonably priced. Praying over the Concise Dictionary

          for Wire is probably not a good use of your time beyond

          expanding your intellectual horizons on the universe of

          wire types.



          Bob . . .

========



Is that the stuff that is  "Flammable producing copious amount of Dense 

toxic smoke (96%+ density) when it burns rendering it virtually impossible 

for flight crew to see their flight instruments." ?



Not that I would be able to afford/obtain anything better, but I'm 

guessing now that's why my flight instructor told me that if I have an 

electrical fire in-air. that I have a poor chance of making it to the ground.


	




   Now, what is the LIKLIHOOD of you experiencing

   an electrical fire with unrestrained propagation?



   I've had a number of responses to the statement

   you quoted above . . . mostly private where the

   writers have cited a litany of net-chatter by well

   meaning but generally unqualified evaluators of

   relative risk. I'm getting ready to be out of town

   until Monday and don't have time to respond to this

   in detail . . . but I'm planning on it. The short

   answer is:



   There are NO insulating materials that produce

   pleasant smoke when they burn. Rubber, PVC,

   nylon, nylon over PVC, or Tefzel. All of the

   chicken-little writers tend to latch onto some perfectly

   valid fact (density of smoke, rise of CO2 in the air,

   alar on the apples, silicone in the boobs, etc) and

   then fancifully translate the fact into a significant

   risk to our health and well-being. Further, after

   having "made their case" they're more than willing

   to legislate the expenditure of a lot of somebody

   else's money to rectify the situation and secure us

   a place in perpetual Utopia.



   These are probably all very nice people to play

   bridge with, or have over for a BBQ but they do

   not have a grasp on the Big Picture and even

   less grasp on the science.



   Last time I checked, the accident investigators

   at Beech were unable to recall ANY serious incident

   ending in badly wrinkled aircraft or people where

   type of insulation )or even an electrically initiated

   fire) contributed to a series of events in an accident

   they investigated. Their archives of information

   go all the way back to cotton-over-rubber wires

   in model 18 and 17 aircraft. In cases where there

   was electrically initiated damage  (of which there

   are MANY) that caused a maintenance event, type

   of insulation on the wires was never an issue.



   Now, if we took the Chicken-Littles seriously,

   we'd have to eliminate fuel and lubricants from

   our aircraft. Under the right conditions, these

   too pose great risk to occupants of aircraft from

   fire.



   The point is that capable systems engineering does

   look at the Big Picture for wires and many other

   potential hazards. Most folks have correctly

   deduced that wires are protected by circuit

   breakers and/or fuses for the express

   purpose of preventing a fire. Likewise, fuels

   and oils are suitably contained. Experience in small

   aircraft going back 100+ years has suggested that

   the folk doing this work have learned their

   lessons well and continue to refine their art

   and science.



   Individuals who would ask you to join them in their

   personal worry du jour on wires (or any other anxiety

   driven discussion) need a more relaxing hobby.

   Invite them over for a six pack or an evening around the

   BBQ grill . . . perhaps you can distract them from

   their worries for at least a little while . . .



   Having said that, there ARE some exotic insulations

   that should not be used and the Big Guys have been

   caught with their pants down because they were sucked

   into the "lighter wire bundles" vortex. But that does

   not included GA light aircraft. Therefore, examples of

   what has transpired in an Air Transport Category a/c has

   little or no significance for our reasoning because

   we HAVE been using the most user and owner friendly

   insulation for wires (Tefzel) for three decades.



   Bob . . .

deej(at)deej.net
Guest

Posted: Thu Oct 04, 2007 11:03 am Post subject: Wire

Robert L. Nuckolls, III wrote:

 	  Quote: 	
		  

   until Monday and don't have time to respond to this

   in detail . . . but I'm planning on it. The short

   answer is:


	


    That was your -short- answer?  *wink*  



-Dj

do not archive



-- 

Dj Merrill - N1JOV

Glastar Sportsman 2+2 Builder #7118 N421DJ

http://econ.duke.edu/~deej/sportsman/



"Many things that are unexplainable happen during the construction of an 

airplane."  --Dave Prizio, 30 Aug 2005

Doug Gray

Joined: 10 Jan 2006
Posts: 112
Location: Sydney, Australia

Posted: Thu Oct 04, 2007 1:36 pm Post subject: Wire

On Thu, 2007-10-04 at 13:27 -0600, Robert L. Nuckolls, III wrote:

 	  Quote: 	
		   There are NO insulating materials that produce

    pleasant smoke when they burn. Rubber, PVC,

    nylon, nylon over PVC, or Tefzel. 


	


See:http://en.wikipedia.org/wiki/Low_Smoke_Zero_Halogen



Zero Halogen cables are mandated for the big black boats and grey funnel

ships I am involved with.  Tefzel is not Halogen free.



Polypropolene is a pretty good insulating material but heavier in

comparable electerical terms and not as tough as tefzel. It is however

more user friendly than tefzel and much more user friendly than teflon.



Rest assured as soon as there is an event where the insulation material

is attributed to the cause of many aircraft deaths we will see ZH wiring

mandated. 



Hmm... tefzel is a registered trademark of which company now?   Then

again perhaps it will not matter how may die.



Doug Gray

mgdurand(at)yahoo.com
Guest

Posted: Fri Oct 05, 2007 6:44 am Post subject: Wire

 	  Quote: 	
		  [b]=========Bob Wrote:         There are NO insulating materials that produce         pleasant smoke when they burn. Rubber, PVC,         nylon, nylon over PVC, or Tefzel. All of the         chicken-little writers tend to latch onto some perfectly         valid fact (density of smoke, rise of CO2 in the air,         alar on the apples, silicone in the boobs, etc)[/b] 	
=========

But then wouldn't wire that has these qualities:



"Resists smoking when burning (less             than 2% density)



Displays all the positive aspects             of Kapton (i.e. lightweight, resistance to burning, no             fumes when burning etc) without any of Kapton's             negatives." [Boeing TKT]



... be better in terms of electrical fire than the one that "obscures vision, etc"?  If cost, etc. were equal that is.



I mean the surest way to "be safe" in  an airplane is to not fly it, but if TKT were the same price wouldn't it make sense to just use that instead?  I.e. go for the marginal or theoretical advantage, like preferring a car with side airbags, or a boat with airtight bulkheads, or boobs with saline instead of silicone....



Michael

RV-7a  with AKZO instead of corrosion X

 [quote][b]

MARVHAMM(at)aol.com
Guest

Posted: Fri Oct 05, 2007 7:21 am Post subject: Wire

There is quite a lot of Teflon insulated surplus wire available on eBay including

 shielded wire at a fairly low cost.

  

 It appears to be high quality -- silver plated wire -- with high temperature limits -- 200 C.

  

 It is my understanding that smoke from teflon insulation is not quite in the same category as smoke from tefzel.  

  

 I am gratified to hear the defense of tefzel, since Bob's arguments make sense.

  

 I know that tefzel is a very tough insulation material.  Other than that, are there any other

 reasons that one might prefer tefzel over teflon?

  

 ....... Marv Hamm



See what'set="_blank">Make AOL Your Homepage.

  [quote][b]

stein(at)steinair.com
Guest

Posted: Fri Oct 05, 2007 8:10 am Post subject: Wire

Teflon jacket with silver plated conductor  is actually pretty poor wire for use in aircraft.  Silver plating isn't  good in high vibration areas as it's brittle.  Teflon wire is slippery, has  poor cold flow tendencies, etc...

  

 Stick with Tefzel and you'll be fine.   Ignore the surplus teflon as well.  It's one of those things that's sort of  "pennywise....but...".  

  

 Chers,

 Stein

  

  

 [quote]   --

Doug Gray

Joined: 10 Jan 2006
Posts: 112
Location: Sydney, Australia

Posted: Fri Oct 05, 2007 2:43 pm Post subject: Wire

Teflon wire is a pig to strip without very sharp tools or hot knife

(Stein - how about adding hot knife strippers to your inventory?). The

risk of cut wire strands is very high.

It's a bit like working with Titanium rather than 4130 or Aluminium.

Doug Gray



On Fri, 2007-10-05 at 11:06 -0500, SteinAir, Inc. wrote:

[quote] Teflon jacket with silver plated conductor is actually pretty poor

 wire for use in aircraft.  Silver plating isn't good in high vibration

 areas as it's brittle.  Teflon wire is slippery, has poor cold flow

 tendencies, etc...

  

 Stick with Tefzel and you'll be fine.  Ignore the surplus teflon as

 well.  It's one of those things that's sort of

 "pennywise....but...".  

  

 Chers,

 Stein

  

  

         --

list(at)toddheffley.com
Guest

Posted: Sat Oct 06, 2007 1:53 pm Post subject: Wire

I have a Kingsley machine with 10 clockwheels, manual wirefeed.



Overly difficult to use for small projects.



I would be willing to sell it to a good home though....



My 2 cents.. Stick with Bob's simple labeling methods, build one end  

of most cables on the bench, run plenty of length and do not do not  

cut the far ends to length until the clamps and ties are tight.



Take extra care to route cables in sensable cable-runs....then reroute  

them a week later because you figured out a better route.



I have done plenty of this work, and sensable wirerouting and  

clampling goes a lot farther than stamped wires.



also, good, hand-drawn prints are more valuable than stamping.



do not archive



todd

nuckolls.bob(at)cox.net
Guest

Posted: Sun Oct 07, 2007 2:38 pm Post subject: Wire

At 05:53 PM 10/6/2007 -0400, you wrote:



 	  Quote: 	
		  

I have a Kingsley machine with 10 clockwheels, manual wirefeed.



Overly difficult to use for small projects.



I would be willing to sell it to a good home though....


	


   I used to have one too. Gave it away about 15 years

   ago . . .

 	  Quote: 	
		  My 2 cents.. Stick with Bob's simple labeling methods, build one end

of most cables on the bench, run plenty of length and do not do not

cut the far ends to length until the clamps and ties are tight.



Take extra care to route cables in sensable cable-runs....then reroute

them a week later because you figured out a better route.



I have done plenty of this work, and sensable wirerouting and

clampling goes a lot farther than stamped wires.



also, good, hand-drawn prints are more valuable than stamping.


	




    Hear, hear!!!!!



        Bob . . .



        ----------------------------------------

        ( "Problems are the price of progress. )

        ( Don't bring me anything but trouble. )

        ( Good news weakens me."               )

        (              -Charles F. Kettering-  )

        ----------------------------------------

nuckolls.bob(at)cox.net
Guest

Posted: Sun Oct 07, 2007 3:00 pm Post subject: Wire

Check out the Teflon vs. Tefzel discussion on pages

38 thru 40 at:



http://www.aeroelectric.com/articles/richter/response_1.pdf



Bob . . .



At 11:06 AM 10/5/2007 -0500, you wrote:



[quote]Teflon jacket with silver plated conductor is actually pretty poor wire 

for use in aircraft.  Silver plating isn't good in high vibration areas as 

it's brittle.  Teflon wire is slippery, has poor cold flow tendencies, etc...



Stick with Tefzel and you'll be fine.  Ignore the surplus teflon as 

well.  It's one of those things that's sort of "pennywise....but...".



Chers,

Stein

--

nuckolls.bob(at)cox.net
Guest

Posted: Sun Oct 07, 2007 3:03 pm Post subject: Wire

At 08:43 AM 10/6/2007 +1000, you wrote:



 	  Quote: 	
		  



Teflon wire is a pig to strip without very sharp tools or hot knife

(Stein - how about adding hot knife strippers to your inventory?). The

risk of cut wire strands is very high.

It's a bit like working with Titanium rather than 4130 or Aluminium.

Doug Gray


	


  Teflon and Tefzel are both stripped very nicely by

  strippers featured at:

http://www.aeroelectric.com/articles/strippers/strippers.html



These specialized stripping blades are described in:



http://www.aeroelectric.com/Mfgr_Data/Tools/stripmaster.pdf

  Bob . . .

deej(at)deej.net
Guest

Posted: Sun Oct 07, 2007 6:44 pm Post subject: Wire

Bob,

	What would you recommend, and where to get a decent set of tools to

work with Molex connectors?  Crimper, extraction tool, etc.



	Christmas is coming up and I'm starting to make out my list...  *grin*



Thanks!



-Dj



-- 

Dj Merrill

Sportsman 2+2 Builder #7118

http://econ.duke.edu/~deej/sportsman/



"Many things that are unexplainable happen during the construction of an

airplane."  --Dave Prizio, 30 Aug 2005

MauleDriver(at)nc.rr.com
Guest

Posted: Mon Oct 08, 2007 5:06 am Post subject: Wire

DJ, I bought a Christmas basket of tools and connectors from Terminal 

Town a while ago.  I don't know enough to recommend anything but next 

time you come by you'll have to take a look.  One connector kit 

contained a good selection of ring terminals and crimp on connectors.  

The other kit a selection of Molex connectors.  All the tools are 

Eclipse brand.  Spent about $400 including some tools I'm sure you 

already have.



Dj Merrill wrote:

 	  Quote: 	
		   



 Bob,

 	What would you recommend, and where to get a decent set of tools to

 work with Molex connectors?  Crimper, extraction tool, etc.



 	Christmas is coming up and I'm starting to make out my list...  *grin*



 Thanks!



 -Dj

nuckolls.bob(at)cox.net
Guest

Posted: Mon Oct 08, 2007 8:32 am Post subject: Wire

At 08:56 AM 10/8/2007 -0400, you wrote:



 	  Quote: 	
		  



DJ, I bought a Christmas basket of tools and connectors from Terminal Town 

a while ago.  I don't know enough to recommend anything but next time you 

come by you'll have to take a look.  One connector kit contained a good 

selection of ring terminals and crimp on connectors.

The other kit a selection of Molex connectors.  All the tools are Eclipse 

brand.  Spent about $400 including some tools I'm sure you already have.


	


  Are the terminals PIDG style. I.e. three piece with the

  metal liners inside the insulation-grip sleeves?



  See:



http://www.aeroelectric.com/articles/terminal.pdf



   Bob . . .

nuckolls.bob(at)cox.net
Guest

Posted: Mon Oct 08, 2007 8:32 am Post subject: Wire

At 10:43 PM 10/7/2007 -0400, you wrote:



 	  Quote: 	
		  



Bob,

         What would you recommend, and where to get a decent set of tools to

work with Molex connectors?  Crimper, extraction tool, etc.


	




    http://steinair.com

    http://bandc.biz



    Bob . . .

        ----------------------------------------

        ( "Problems are the price of progress. )

        ( Don't bring me anything but trouble. )

        ( Good news weakens me."               )

        (              -Charles F. Kettering-  )

        ----------------------------------------

MauleDriver(at)nc.rr.com
Guest

Posted: Tue Oct 09, 2007 9:56 pm Post subject: Wire

Yes they are.  Both the ring terminals and the splices are 2 pieces of 

tinned plated copper with a plastic sleeve.  Looks like the knife locks 

are too.  There is a selection of ring terminals for both various wire 

sizes and post sizes.  They are all listed according to "mil spec" codes 

such as MS-25036-102 for a #6 ring and 22/18 AWG wire.  The AV/24 - 

Aviation Electrical Maintenance Kit from Terminaltown.com is in a nice 

metal case with 24 plastic labeled compartments with ring terminals, 

splices, wire caps,  and knife locks.  It was $200.    The 'Molex' kit 

with crimper was $90.  Don't know how those prices compare but it was a 

good start for me.

Thanks for the lesson and the link to your pdf.

BTW, B&C and Steinair are my main suppliers but I found TerminalTown to 

be a good supplier of this kit and a few other OBAM oriented items.  I 

think Wm Curtis had mentioned them in a post.

I'm not affiliated with any of the above.

Bill "still wiring my RV10" Watson

Durham NC

Robert L. Nuckolls, III wrote:

 	  Quote: 	
		  > DJ, I bought a Christmas basket of tools and connectors from Terminal 

> Town a while ago.  I don't know enough to recommend anything but next 

> time you come by you'll have to take a look.  One connector kit 

> contained a good selection of ring terminals and crimp on connectors.

> The other kit a selection of Molex connectors.  All the tools are 

> Eclipse brand.  Spent about $400 including some tools I'm sure you 

> already have.

> 

> <MauleDriver(at)nc.rr.com>

   Are the terminals PIDG style. I.e. three piece with the

  metal liners inside the insulation-grip sleeves?

  See:

 http://www.aeroelectric.com/articles/terminal.pdf

   Bob . . .

Display posts from previous:

	Matronics Email Lists Forum Index -> AeroElectric-List	All times are GMT - 8 Hours
Page 1 of 1

Jump to:

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