Step 15: Nut and 5th String Nut

Picture of Nut and 5th String Nut
The nut is anything to hold the strings off the neck at the head end and keep them from sliding sideways. Traditionally it's a rectangular rod of bone with some notches sawed in it.
A brass button-head slotted screw is traditional nut for a banjo fifth string.
Here you see a "zero fret" and some nails acting as the nut.

I tried to play my accidentally left-handed banjo but it hurt my brain. So I reversed the strings back to right-handed order. Then I reamed a peghole on the correct side and hung the fifth string there, with a nail to prop it up to the correct height. I rarely fret this drone string, so it's okay that it's not over the neck its whole length.