I've noticed that many folks can easily make a few inches of nichrome glow by using various power supplies they have on hand, but that's not been my experience. I've tried a 24V 3A bench power supply, a 19V 4.7A laptop charger, and a 12V 3A wall wart—only the wall wart actually heated the wire. According to Jacob's calculator, I should be using around 2.3V at 4.5A for effective heating. Could my higher voltage supplies not be suitable? I'm open to purchasing a recommended power supply, but I'm confused why my existing ones aren't working. I'd rather not cut up more supplies, yet I want to avoid buying extra barrel connectors for non-functional setups. It seems my understanding of the necessary power supply specs might be off.
2 Answers
Remember, you need current at low voltage to heat the wire effectively. Something like an old PC power supply’s 5V rail could be a good match for what you’re trying to achieve!
It sounds like your 24V and 19V supplies might have short or overload protection that kicks in when trying to work with the nichrome. I personally use a hefty 10A 15V linear power supply that doesn’t have that protection, which allows me to adjust the voltage appropriately for cutting foam. You might want to consider investing in something like that—it really helps dial in the right cutting temperature!
Thanks for the tip! Looks like I might have to buy a power supply that's specifically built for this kind of work.