Soldering flex cable

[SweetAccord]

Why solder or use any heat method when you can put JB Weld and sand it down nice and smooth for the motor coupler side? It won't turn out as soft as any solder (which they all are) and it will not have any heat effects or unwind the end and is hard as a rock and won't crack?

[ray schrauwen]

First you cut it nice and true. https://youtu.be/jW-VSCDe-_E

Then tig weld up the end to keep the center core locked in place and regrind the end.

TIG is the way to go if you do anything to a cable.