Fret Placement for Nicotina
These fret positions are for a vibrating string length of 68.28 cm, which is about right for banjo strings. (The fret locations also happen to match the fret positions on my favorite dulcimer. I go with what I'm happy with.) If you want to make the vibrating portion of the string longer, just use the computer program, and don't forget to add in enough length for the head and tail of the instrument.