Date: Sun, 31 Jan 1999 18:43:52 -0800
Reply-To: Karl Batzler <KBatzler@EMAIL.MSN.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Karl Batzler <KBatzler@EMAIL.MSN.COM>
Subject: Re: Soldered Connections...Not!
Bill said:
>So where do you get copper crimp on connectors? I think the only ones I've
>ever seen for sale are aluminum (?). And many that came stock on vehicles
>appear to be aluminum. But they don't seem to corrode.
>Bill
That's because the copper crimp connectors are generally coated with nickel
or zinc to prevent corrosion.
Karl Batzler
84 Vanagon
87 Audi 5000 S
La Quinta, CA
-----Original Message-----
From: Davidson <wdavidson@THEGRID.NET>
To: vanagon@GERRY.VANAGON.COM <vanagon@GERRY.VANAGON.COM>
Date: Sunday, January 31, 1999 10:02 AM
Subject: Re: Soldered Connections...Not!
>So where do you get copper crimp on connectors? I think the only ones I've
>ever seen for sale are aluminum (?). And many that came stock on vehicles
>appear to be aluminum. But they don't seem to corrode.
>Bill
>90 Westy Syncro
>-----Original Message-----
>From: Carl Turner <CarlMarin@AOL.COM>
>To: vanagon@GERRY.VANAGON.COM <vanagon@GERRY.VANAGON.COM>
>Date: Sunday, January 31, 1999 9:43 AM
>Subject: Re: Soldered Connections...Not!
>
>
>>David Writes:
>><<<<<<<
>>Subject:Soldered Connections
>>I think you are missing the point with soldering - or you have never seen
>>it done correctly. Your examples of failing solders are not from a wire
to
>>wire connection but a wire to a component / circuit board connection. If
>>you are soldering two wires together you must do what is called a "western
>>union" connection first. This is where you strip the wires say 1.5 to
>>2.0cm and put them parallel to each other so the cut end of one wire is
>>next to the begining of the plastic covering of the other. Then twist the
>>wires so they make a mechanical connection first. The wires should be
able
>>to hold together without solder. The next step is to do a propper
>>soldering job where you heat the wire and not the solder thus advoiding a
>>cold solder. Use decent solder that contains a very small amount of flux.
>>I use the Radio Shack stuff. After you make this connection I will bet
>>anyone one hundred bucks that it will NOT break. If you waterproof it
with
>>lithium greese and seal it with very snug heat shrink it is almost as good
>>as an uncut wire - just a little stiffer where the connection is made.
>>
>>Crimps do have their place and work well when done with the right tools.
>>They do tend to leave some part of the connection open to the atmosphere
>>which makes it prone to rust and eventually failure.
>><<<<<<<<<
>>
>>I'm afraid you'd loose that 100 dollars David! Soldered connections used
>on
>>equipment subject to vibration, cars, airplanes, rockets are especially
>prone
>>to fatique failure. The type of soldered joints used on connectors and
>>splices in the mil-spec environment are highly speciallized and the specs
>for
>>how these wires are then harnessed and strain relieved are very specific.
>The
>>wiring on our Vanagons doesn't even come close to this standard. Most
>wiring
>>on General Aviation aircraft and most experimental homebuilt aircraft (as
>Ken
>>W. alluded to) is done with proper solderless crimp connections.
>>
>>A proper solderless crimp connection fits a proper size crimp fitting to
>the
>>gage wire, is compatible in material, ie copper on copper wire, aluminum
on
>>aluminum wire and so on. The joint is then "sealed" as it were with a
>>generous length of shrink wrap that not only keeps out corrosive
>environment
>>but also serves to strain relieve the joint. One problem common to us all
>I'm
>>sure is working with the crappy crimp connectors they sell down at the
>local
>>flaps. They usually have some plastic cover with huge water catching cups
>on
>>the ends. I never really figured out what the point of those were. I
>often
>>just cut the plastic cover on these type of crimps off, slide one or two
>>lengths of shrink wrap on the wire before crimping, do the crimp thing,
>slide
>>the heat shrink over the joint and warm it up ( proper heat gun, not a
hair
>>drier or a match please!) Resulting joints stay dry, and maintain the
>>ductility of the base wire and should not corrode if you used the proper
>>material crimp (remember dissimilar metals corrosion?) If the wire you
are
>>connecting is grubby, it should be cleaned with some scotchbrite before
>>crimping. Really, the key to neat and tidy crimp connections is using
>shrink
>>wrap over top of them. Those blue and yellow plastic covered things they
>sell
>>at the auto parts store do not make for neat connections unless modified
as
>I
>>described above .
>>
>>Now to the problems with soldering. Soldering can be used to solve
>connection
>>problems certainly. For example, you can't get a good fit for a crimp
>>connection or you are joining wires of different gage or you can't get the
>the
>>store to buy the right crimp connections (I've been there, believe me!).
>So
>>what you want to do is try and create a solid mechanical connection before
>you
>>solder by twisting the wires together or whatever (or dare I say...use a
>crimp
>>sleeve) You then want to use a minumum amount of solder, not so much that
>you
>>coat the joint with a shiny blob of metal (I know, it looks good but its a
>bad
>>idea). What happens is the multistranded wire wicks the solder up along
>the
>>length of wire well away from the joint making that length of wire very
>>brittle and prone to fatigue failure. The flux gets wicked up even
further
>>into the wire where it can have a corrosive effect over time (even rosen
>>flux). Just take a bit of wire scrap and solder a really big blob of
>solder
>>to the end and really burn that baby in. When cool you'll be able to
>actually
>>feel how the wire has been stiffened under the insulation where the solder
>>wicked up. So if solder you must, practice on some scraps till you can
get
>>the 1/4 inch at the end soldered but can still flex the wire beyond the
>>soldered bit. You're on the right track now for an acceptable soldered
>>connection. The joint should now be shrink wrapped, maybe a couple of
>layers,
>>each a little longer than the one underneath, to give a nice strain relief
>to
>>the wire. The wire should now be strain relieved with proper clamp in the
>>installation so it isn't buzzing as you roll down the road or fly through
>the
>>wild blue yonder (depending on your personal conveyance of choice). As
>>further argument in favor of my assertion, notice that all automotive
>wiring
>>used multistranded wire rather than single solid wire conductors. This is
>for
>>flexiblility and thus longer fatique life. By soldering your
multistranded
>>wire and binding up the strands for a significant length you are creating
>>something that looks like solid single conductor wire. Anybody wiring
>their
>>cars with Romex?
>>
>>Carl Turner
>>
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