Date:         Sun, 31 Jan 1999 00:17:37 -0800
Reply-To:     Otmar Ebenhoech <Otmar@EVCL.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Otmar Ebenhoech <Otmar@EVCL.COM>
Subject:      Re: Soldered Connections
In-Reply-To:  <3.0.3.32.19990130233858.0112cfe4@mail.abccom.bc.ca>
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At 11:38 PM -0800 1/30/99, David Marshall wrote:
>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.

Maybe I was misdirected here, I was thinking of a crimp joint to something
like a 1/4" faston connector for going to the back of the light. You are
right that I was thinking of a wire to component connection.

I would agree that in the case of wire to wire connections, using a western
union connection in a non flexing area it would be a very good connection.
This used to be done in the ECU harnesses of some cars (I think I remember
them in a '87 ford), but in my 97 jetta harness they were crimps.

The lithium grease trick sounds good (if messy). There exists a type of
heatshrink that has a sealer inside it to seal connections from the
atmosphere. Usually it's called high voltage heatshrink and I've seen it in
three weights. Basically it's heatshrink with a hot glue like substance
inside it that oozes out when it is shrunk. This is fantastic stuff for
both crimped and soldered joints. Unfortunatly it's quite expensive. You
can make your own by laying down some hot glue on the joint and then using
ordinary shrink tubing over it. When the tubing gets hot enough it melts
the glue. Makes for a great sealed joint, but it will eventually crack and
compromise the seal if it's flexed enough.




 -Otmar-
86 Syncro (front) 82 (rear) Stretch GTI Westfalia. "Power of two"
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