Another method of wiring connectors with lots of contacts is resistance
soldering where a tweezer-type tool heats the connection with a very low
voltage, moderately high current that passes thru the contact's solder cup,
creating very localized heat.

The wire ends are stripped and tinned, and the solder cups at the ends of
the contacts are tinned and partially filled with solder.

The tweezers are "pinched" onto the contact (each side of the solder cup),
the resistance soldering station is energized (foot switch, typically), and
the tinned wire end is pushed into the molten solder puddle in the cup as
the heat increases to the flow temperature of the solder.

The current beiefly passes thru the contact, solder and wire end until the
operator releases the foot switch, and then moves the tweezer tips to the
next solder cup to repeat the process.

The tweezer tips only need to be kept clean (not tinned) so they can provide
a good electrical connection with the contact or terminal to be soldered.

Te resistance soldering station provides a line/mains-isolated low voltage
from a transformer that may have a variable duty cycle triac circuit, to
adjust how fast the heat is generated in the contact.
The variable duty cycle allows the operator to adjust/tune for different
sized connections (very light duty for miniature contacts, or more sustained
current cycles for heavy duty terminals).

--
WB
..........


"axolotl" wrote in message
...
On 11/3/2010 11:36 PM, Karl Townsend wrote:


I just selected a bunch of solder type from digikey. I'll hire it out
locally. I don't even try to solder anything smaller than #18 wire and
it has to be to a through hole type pin. Its a skill I was poor at
years ago, and I got worse.

There is another assembly option. Some places mass terminate solder cup
type connectors using solder sleeves- a short piece of shrink tubing with
a stripe of solder paste on the inside (Raychem is one manufacturer). Put
the connector in a vise, put a solder barrel over each connector solder
cup, strip the wire and poke it down into the desired solder cup. The
solder barrel is able to hold the wire in place until all the wires are
positioned. Hit the connector with a heat gun. The solder barrels shrink
and the solder paste inside them melts, flows, and makes the connection.
You end up with tight insulated connections.

Kevin Gallimore