I made one of these when I was young, poor, homeless, and imminently dying due to being swiftly being frozen to death (with bone tumors coming in second place in the death race). I was able to get an abandoned metal shead with a small heater working quickly in a sudden ice storm using on hand parts and a pirated "outside" power line.
Outside of a significant situation like that... it's not a good idea
I mean he'll, in high school residential electricity class we had one of these for testing our walls, one time it burnt out a wire and the teacher only let me fix it as I was the top of the class, mind you we were only a class of 6 so...