In MMD 070723 George Kiriakidis asked for pins for restoring a Turconi
barrel piano (called "Laterna").  I have a similar instrument made by
Turconi, as well as an Italian street piano, which I was restoring some
years ago.  At that time I had the same problem when I was looking for
the spare pins.

I found some suitable steel pins, of 1.5 mm diameter for the Laterna
and 2.5 mm for the street piano (both very close to the original
diameters).  These pins are "nails without a head" and are made from
hardened steel, 25 mm long.  Where I had to use tapered pins, I ground
them, one by one.

For the street piano I had to replace about 3500 pins which were worn
down.  It was a terrible work to prepare and to insert all these 3500
pins manually into the barrel of the street piano.

For the Laterna much fewer pins had to be replaced, but there was
another problem: the length of the pins standing out of the surface of
the barrel was different, depending on the loudness that the note should
sound.  I could not exactly reconstruct the original length of the pins
and so I had to do some guessing, but the final result sounds good.

George mentioned that some of the original pins are round, others are
square.  I think that this is not the original situation and will not
effect the sound of the notes in any way, but it might come from a
former restoration.

Good luck, George!

Greetings from Germany
Christian Greinacher