Nichrome wire rope cutter Answered
I've recently started working on a nichrome wire rope cutter. I've built a prototype that uses 2 9V batteries that connect in parallel to a 2" piece of 24 AWG nichrome wire. It works, but burns through the batteries within a minute of running them before they don't output enough current to heat up the wire.
I would like to improve this by turning it into something that is much less likely to burn itself down, or electrocute me in the process. I've been looking into ac to dc converters so I don't burn (almost literately) through 9V batteries. I'm kind of a bit hung up on the electrical engineering portion of this however. If I were to use something like a 12V 5A power supply, and then nearly short it with the nichrome (a resistance of .2477 OHMs) is the adapter limited to 5A, or would something start to melt. I have a feeling I need another resistor in there to reduce the current (if I but a larger PS), and or a potentiometer to dial in the temperature.
Any help would be appreciated.