by orphanespresso on Mon Feb 01, 2010 5:02 am
Peacecup, heaven forbid you would think I of all people would be advocating pump machines over levers....I was just making the point, or trying to, that one step sometimes leads to another and it is all thought to be progress.
Every time we go through another early machine, and it is a learing experience each time, it causes me to ponder the entire issue of why the machine was designed as it was, throwing out all other ideas and gravitating to a single general design. Piston, cylinder and pf size (but for La San Marco), spring operated lever, etc....but all pretty much the same group design. Think about Achille Gaggia and his Crema Caffe idea and imagine that you are the one working out this 14 grams coffee at 94C under 9 bar pressure pulled 25 ml in 28 seconds. Pretty high degree of specificity there to just stumble upon.
The dosing and grinding had been pretty well worked out in the verticale machines as just what made for a good cup of espresso, but the 9 bar made the crema. How to deliver the 9 bar. I reject the ergonomic idea and pity the poor barman with repetitive stress injuries (such concepts asrepetitive stress injuries did not exist then.....they were a part of life), and any touchy feely ideas about ergonomics are pretty much obviated by the continual use of stoop labor to plant and harvest our fresh market crops, so I think that in 1948 there was likely not much thought of the barman who would have to pull a lever all day long since he was lucky just to have a job anyway. After all, the piston could have been foot operated, which would have done away with that argument alltogether and been very simple to kick down on a pedal linked to the piston, or use a counterweight system for compressing the piston in the cylinder. I think that Gaggia found that he needed a force multiplier of some kind to get the pressure up for crema and just had a eureka moment when he hit on the spring, even though his first machines had a clockwork type mechanism for the power.
Since this is more or less lost in the mists of time I just have to think that the spring was such a good idea at the time that it just stuck and was seen as the best way to manufacture the machine for this wonder process. Like the internal conbustion engine, it just became the way it was done.