Numerical control tooling-machines for tuning.
Some hints about the story of Bezzera
who created the history of espresso
coffe: the use of steam in the first machines
was replaced by water and today by
dispensing groups operated both
manually and by solenoid valves.
What never changed,
even after nearly a century, is
the "filter-holder", being the heart of
Bezzera's original patent.
Boiler-soldering dept
Details of assembly: testing and finishing.