I managed to cut the cord on my skill saw. As I’ll need it for my deck project, I had to fix it. Here’s how. You need a knife (wire strippers or even cutters are better), soldering iron, solder, electrical tape, and duct tape. Here’s the starting point:
After cutting it, carefully remove about an inch of the outer sheath, being careful not to cut into the wires inside.
Next, carefully strip about 3/4 of the insulation of each of the wires.
Splice the matching pairs together with a lineman splice. Twist the wires about 1/4 of the way out from the insulation, then wrap each about the other, twisting them in opposite directions:
Solder the splices to make a solid connection:
Wrap each splice in electrical tape, being sure to cover the insulation on both sides.
Finally, wrap the splice in duct tape, making sure to wrap the outer sheath, so that if the cord is pulled on, the duct tape will take the force of the pull: