danno wrote:Stupid question, perhaps, but the La Peppina is so bizarre and compelling that I just have to know how it does what it does.

Does pulling the lever load the piston spring in the bottom, introduce water into the cavity, and then force it up through the grouphead via spring pressure? Do you have to maintain lever pressure all the time? How do you know when the water is at the right temperature?

I love the design. If it were orange it would remind me of a Seventies fondue machine gone askew on th' treadle. Oops, sorry for letting a little Monty Python sneak in.
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They also come in that 70's orange.

The water goes down into the column, entering the cylinder at the bottom when the lever is pulled down, and the piston clears the entry holes. Then the piston pushes the water up into the group.

Apparently, there were quite a few gravity fed lever machines made, for instance, another home model by Gaggia and a commercial one by Conti. These have the advantage of allowing a perfect temperature control since the tank can be regulated. The big killer on dual boilers is that the boiler refills with cold water when the shot is made, requiring complex preheat piping. Since these machines don;t refill, the temperature is dead stable. On mine, the shot temperature is about 1C below the tank temperature when the group has been preheated with a flush. The disadvantage is they require a second boiler for steaming.

The original Peppina version had no steamer-attachment, that was added for the US importer. A few years later, the models were upped from 700 to 1100 watts, since the steaming pretty much sucks on the 700 watt version.

Thanks for the correction. This is a bit more elaborate than I expected. Many of these machines had no valves, just holes at one end of the cylinder, once the piston was past them, the exit was sealed.