Here we will consider the manufacture of two types of copper tips for different soldering irons. One soldering iron has a locking screw for fixing the tip; the tip is screwed into the second soldering iron. The author makes stings of copper wire with a suitable diameter cross-section.
First you need to straighten the wire (if it is bent, of course) and cut a piece of 65 mm.
Then you need to clean the workpiece. The author does this in a drilling machine. Installs the workpiece in the cartridge and polishes it with a metal sponge, and an emery cloth. During grinding, the tip diameter is adjusted to the diameter of the soldering iron socket.
A file gives the tip the desired shape. Now it remains to insert the tip into the socket of the soldering iron and tighten the locking screw.
The manufacture of a threaded tip is similar, with the exception of some details. The sting length in this case is 2.5 cm. A thread is cut on one side of the workpiece.
Further, in order not to damage the thread, it wraps the threaded edge in aluminum foil (from the beer bottle), clamps it into the machine chuck and grinds it.
That's all, now it remains only to screw the sting.
In principle, the tip can also be made for modern soldering irons, in which the tip is inserted into the tube and clamped with a nut. The only thing there will be to drill a blind hole, the corresponding diameter.