Bendandi was born in Faenza to a family of modest wealth. He only attended school for five years, but at the time of the solar eclipse of 30 August 1905 became interested in planetary motion in the solar system. He worked for a watchmaker and an engraver, and also attended a technical drawing course, enabling him to make precision instruments and drawings to explore and demonstrate his theories. After the 1908 Messina earthquake, he began studying the tides, and also devised his own form of seismograph. In October 1914 he predicted in his unpublished notes that an earthquake would take place on 13 January 1915 and, after the Avezzano earthquake did occur on that day, killing 30,000 people, he devoted much of his time to studies of past earthquakes and planetary alignments, setting up his own observatory with seismographs.