There’s everything from a table of design requirements to quick but thorough explanations of nichrome wire and basic electronic theory. And then there’s the material consideration.

[Techgenie]’s handheld hot wire foam cutter is a simple build based on a single 18650 and a piece of nichrome wire. While this is probably not the most Earth-shattering hack you’ll see today ...

When a length of copper or nichrome is heated, it lengthens due to thermal expansion. The wire is suspended between two posts and heated by a variac. A small weighted hook is placed in the middle of ...