Probably born in Venice around 1712, Dacci was the son of the shoemaker Pietro Antonio (originally from Chironico in the Canton of Ticino) and Anna Meneghini. He began working in organ building in his youth under the guidance of the Dalmatian master, Don P. Nachini, who in 1751 saw him as his best pupil. Dacci succeeded him in the prestigious Nachini workshop, located in Barbaria delle Tole in Venice. He spent most of his career under the shadow of his master, and only after 1763 did he begin to sign his works alone, which were mainly located in the regions facing the Adriatic Sea. He married Paolina Davanzo around the mid-century, with whom he apparently had no children, and died in Venice on January 1, 1784, leaving his artistic legacy to his nephew, Francesco Antonio Dacci.

In Friuli, along with Nachini, he signed the organ of the parish church of Tricesimo (1752 op. 174, now in the parish church of Madrisio) and that of Madonna del Giglio in Aprato di Tarcento (1761). The last two organs resulting from the Nachini-Dacci collaboration were completed in July 1763 and were located in the church of S. Francesco della Vigna in Udine (now in the parish church of Fogliano) and in the cathedral of Tolmezzo (which was modified and modernized several times). The construction of two organs in the city of Udine dates back to 1765: that of the parish church of S. Cristoforo is still in use, while the one located in the church of Zitelle was partly incorporated into a newer instrument by Beniamino Zanin. The construction of the large organ of the parish church of Gemona was decided in 1768 but was only completed in March 1774; equipped with a small response organ, it was almost completely destroyed by the collapse of the right nave of the cathedral, caused by the disastrous earthquake of 1976, but the patient restoration carried out by Franz Zanin allowed the instrument to regain its ancient splendor and original sound. In 1769, Dacci placed two organs in Buia: that of the church of S. Stefano was dismantled in 1961, while that of the Beata Vergine at Melotum in Madonna was saved from the devastating fury of the earthquake. The organ of Treppo Grande (1770) was also recovered and restored after the earthquake; the two-manual organ of Marano Lagunare (1774) originally had a splendid case, unfortunately demolished in 1959. Other instruments attributed to Dacci, such as those of the parish church of S. Quirino in Udine (1774) and the cathedral of Sacile (mounted in January 1776), no longer exist; finally, it should be noted that in a letter from October 1775, the Venetian master stated that he had to deliver an organ to Zugliano (a location on the southern outskirts of Udine), but no further documentation of this instrument has been found.

https://www.dizionariobiograficodeifriulani.it/dacci-francesco/