At the bell foundry Jan Felczyński in Poland, the largest swinging bell in the world was cast in the summer of 2017. The 'Vox Patris', as the bell is called, is destined for the new 'Basilica do Divino Pai Eterno' in Trindade, Brazil. The bronze bell (78% copper / 22% tin) weighs 55 tons, is more than four meters high and has a diameter of 4½ meters. The clapper will weigh about two tons. Four linear motors are required to set the bell in motion.
The first casting attempt in November 2016 failed because of a small crack in the mold, but this time everything went smoothly. The bell was cast within twelve minutes. This corresponds to a speed of 150 kg of bronze per second. The strike note of the bell is a very low F-sharp with a frequency of 92 Hz. The fundamental will probably be below 40 Hz: you will feel the bell before you hear it. The bell is decorated with images from the history of the pilgrimage site in Trindade and with flora and fauna from Brazil. Felczynski will also cast 68 smaller bells for the basilica. The bells are transported to Brazil by ship. If all goes well, the bell will be placed in a new 100 meter high tower near the basilica and sound for the first time in 2020.