I present to you a vintage Black and Decker ¼ inch drill. When I first looked it over and saw the metal case, I though. “Wow, there’s an antique tool. Don’t see those every day. Probably electrocute you if you plug it in.” In fact, the outer insulation of the cord was broken where it met the body of the thing and you could see lots of cloth and paper insulation peeking out.
So I pulled out a multimeter and checked the continuity between the prongs of the plug first. I figured there should be no continuity until I pull the trigger and then there should be continuity. But there was a beautiful electrical path between the two prongs, even without pulling the trigger. Exciting! Then I tested for continuity between each prong and the metal out shell of the drill. Perfect continuity again! Everything was electrically connected to everything else.
I couldn’t see any bare wires in the frayed part of the cord, so I started taking the drill apart. The screws were a little stripped, like somebody else had done the same thing decades ago. Once I got it apart, I was appalled to see that it was even worse than I expected. The cord could twist freely where it passed through the grommet, and I could se that it had.
The power cord had lost all its insulation just on the inside of the grommet, and the hot, neutral, and ground were all bare and twisted around each other.
You could see that there was a clamp on the cable after it penetrated the body of the drill to keep it from pulling out. That’s good. But there was nothing to keep the cable from twisting, and it had twisted around itself a lot. I untwisted them just to see how bad it was. At least an inch of bare wire on each conductor. And it wasn’t even copper wire. The wire was aluminum.
So I cut the cord off the thing so nobody in the future would plug it in. I thought I might cut the cable back to some fresh spot and re-use it, but the cable insulation was was breaking everywhere as I tried to straighten it out. Looking at the cable, that’s when I fully realized that the plug was a two prong plug, but the cable had a ground wire in it too. Coming out the back of the plug was a green ground wire that had been cut off years ago. I’ve never seen that before.
I guess, you were supposed to wrap the ground wire around a pipe or something before you used the drill?
