Actually, a very hot soldering iron or gun is the answer. I used to use a Weller 250 watt pistol grip solder gun to repair printed circuits on dash panels. Get the gun running full hot, quickly apply the tip and the solder just long enough to tin the wires, and pull away. There's not enough time for a long section of wire to overheat. Lower-heat irons need to stay in contact with the connection longer, and a bigger area gets to critical heat. Be sure to uase rosin-core solder, not acid core.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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