Date: Mon, 12 Jul 2010 23:36:28 -0500
Reply-To: Tom Hargrave <thargrav@HIWAAY.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Tom Hargrave <thargrav@HIWAAY.NET>
Subject: Re: How to deal with short ALT cable
In-Reply-To: <0929F685-8D42-4CA8-B834-F251C9E18B1C@shaw.ca>
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I agree 100% about good quality connectors.
Unfortunately a lot of people pick up the cheap connector kits at Harbor
Freight and everything in the kit is junk. There are a lot of great deals at
Harbor Freight but not the electrical stuff. Unfortunately I also see a lot
of the cheap stuff filtering into the Mc-Parts stores. Everything is so
price conscious that they will skimp on just about anything.
These days if you don't know enough about connectors to sort good from bad
and you want good crimp connectors you just about have to go to the walk-up
counter of a business like Graybar and buy a box. They won't be cheap but
they won't be junk either.
Tom
www.towercooler.com
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@GERRY.VANAGON.COM] On Behalf Of
Alistair Bell
Sent: Monday, July 12, 2010 10:56 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: How to deal with short ALT cable
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.
