A 3D-printed hollow tube has a wire ferrule inserted in the end ... If more slack is required in the solder feed, one simply pins the solder down in the device and tugs to draw more out.

Holding through-hole components in place while soldering is a pain — literally. I’ve mildly burned my fingertips numerous times holding components (like pin headers) in place with one finger ...

However, it's toxic and bad for the environment. Many solders contain a rosin core, which aids in cleaning the wires you're ...