q about hotwire =) can i use a 18650 battery to run this thing instead of plugging in the wall….maybe add a momentary switch??? thanks in advance…
I'm not entirely sure what a 18650 battery is, I'm assuming it's a 3.7v Lithium Ion battery? In that case, the short answer is no, it won't really work.
I have a whole section dedicated to fixed voltage power supplies and batteries. Check out this link.
The problem with batteries is that they are a fixed voltage power source, so you can only regulate your wire temperature by adding a resistor or altering wire length. The second, is that not every battery can withstand or is designed to output currents/amps necessary to heat nichrome wire. With most NiCr wires requiring ~3-4 amps to cut effectively, it is typically not possible with most batteries.
I do have a few battery sources listed on my website as well. Linked here. Again, the problem is fixed voltage. You'll only be able to moderate wire temperature by changing the wire length. That may or may not work for you and your design!