Date: Mon, 12 Jul 2010 20:55:55 -0700
Reply-To: Alistair Bell <albell@SHAW.CA>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Alistair Bell <albell@SHAW.CA>
Subject: Re: How to deal with short ALT cable
In-Reply-To: <4c3bb7fc.625ae50a.704f.ffff8e2f@mx.google.com>
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ah the perennial crimp vs. solder question. Its a real debating point
and has reasoned support on both sides.
my 2 cents...
A good crimp is best in car for these reasons:
(based on using proper crimper and good connection hardware)
1. its relatively flexible
2. makes a very good electrical connection
3. easy to do
A solder connection is good in that it excludes moisture at the
joint, something important in marine applications. But it can make a
"hard spot" that might cause the wire to fatigue just outside the
solder joint. Mind you, a good solder joint is not always easy to
make, especially in situ so to speak.
All that said, I used to crimp and then solder in the wiring work on
the van. But I would use heat shrink tubing, often in staged lengths
so that there was not one localised flex point.
But now I just crimp because its easier :)
one thing that is important no matter what method you use, and this
can not be over emphasised, that is use good quality connectors. Not
the bargain brand stuff, but the more expensive kind. Talking about
male and female spade and molex type connections. Cheap connectors do
not have the same spring in them and do not make a solid mechanical
connection.
Even in ring and fork connectors where a bolt or screw makes the
connection, good quality connectors are really worth the money.
cheers
alistair
On 12-Jul-10, at 5:48 PM, David Beierl wrote:
At 07:35 PM 7/12/2010 Monday, Raymond Paquette wrote:
> But, when I solder stranded wire on a car, my connection often breaks
> off (after a time).
>
> The wire is flexible, with strands that move independently from each
> other, so there's no one spot that takes all the flex.. The solder
> creates a solid mass with one flex point where the solder ends.
>
> FWIW, and not diminishing my overall awe at the wisdom of the
> collective.
Rem acu tetigisti.
Your observation is correct (and you have opened up a can of
worms). The pros and cons of soldered vs crimped connections, and
the correct technique for soldering a wire that will be used under
vibrating conditions can be researched voluminously on the web; and
you've put your finger on exactly the trouble spot.
Let the contest begin...in gentlemanly fashion of course. I'll throw
my hat in and say that it takes a great deal less specialized
knowledge to make a good crimp joint than a good solder joint in
wires that will be subjected to mechanical stresses, particularly
vibration and bending stresses.
Yours,
David
ps -- many years ago I had a catalog which listed a thirty-dollar
pair of beryllium-copper "anti-wicking tweezers" to clamp around
20-ga stranded wires for soldering to NASA specs. Thirty dollars was
quite a bit more then than it is now.