Once again my long winded typing got me thrown out. To summarize I wrote,
Marc was absolutely right. I knew the info was right despite citing knowledge
of out dated solder spec certificates. The arguments around FAA ruling had to
do with whether or not crimping stranded cable increased risks of breakage and
whether solder could withstand severe temperature variations between sub
freezing temps to melting points of solder when power exceeded rated limits.
The prohibited use of solder in specialized circuits like thermo-wiring and
such precedes it's usage in other applications; although it is my understanding
that soldered connections were prohibited in most high power use since my cert
days. The specs still call for tinned leads (fabricated cables pre-tinned by
the manufacturer). The terminals used in aviation require specialized tooling
and is subject to inspections.
In an application of car usage, although some cars are left to brave -30F
temps, even with a 600-900A start up current, it will not heat a 1ga cable fast
enough to the point of causing solder failure. Waivng other extreme aviation
concerns some of the old arguments for soldered connectors can be cited.
Unless crimped connections are under the scrutiny of aviation standards,
chances are the untrained (even trained as I was) are most likely to lack the
proper tools and more or less just "smash" the terminal onto the cable end.
Without the compression like crimp, the strands inside the connector are left
w/o contact to metal; therefore, increasing resistance and is subject to
degrade by corrosion (acid corrosion, tarnishing,etc).
An extreme example of the above... I used those 2 bolt clamp on terminals as an
example. Greatest invention ever, a must have to keep on hand, however I'm
almost certain everyone that has used them know they immediately let the copper
corrode, and eventually need to be reset or replaced within 3-12 months.
On the other side of the aviation concern, is a fault that you might want in
your car. If for some reason the battery cable shorted to ground, I would
rather have the solder melt off (and hopefully break connection) before the
insulation melts and the cable glows red (although not very likely with 1ga and
"if" 600A sustained, not before the terminals melt or the battery explodes
anyway). If solder failure is a concern, it is easy to inspect 2-4 points in a
car where aviation concerns have to worry about hidden wire splices and
inaccessible terminals... and don't forget possibilities of crimping and
soldering =)
In any case the object of the terminal to cable connection is to maximize
current transfer (by direct conductor to conductor contact to lessen
resistance) and protect the copper from corrosion. Solder in this case is
optimal, however is subject to some of the aviation concerns of failure, namely
sub zero temps w/ heavy vibrations. with a correct fitting connector and
soldered properly, to my knowledge, failure is not likely under ground level
extremes.
I mentioned welding cable as Mike did. Battery cable is made of wound strands
of 18-16ga wire where welding cable is made of 24-30ga strands, making it much
more flexible. In both applications make sure they cables will meet or exceed
any chemical, heat/cold, UV exposure and abrasions concerns.
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