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Permalink Reply by Brady on March 7, 2010 at 2:48pm

Parts diagrams for the more common machines are pretty easy to find on manufacturers' websites. Here's a link to the LM page, which has lots of parts schematics on it:
http://www.lamarzoccousa.com/New%20LM%20USA%20Website_files/page000...

I suspect that full schematics for the more advanced machines that you listed are a little harder to come by.

Hope this helps.

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Permalink Reply by Mike Sabol on March 7, 2010 at 3:56pm

Hi Victoria. Those machines are quite beautiful. I can see why you'd choose them to look further into. But your question is actually a pretty broad one so my first answer is going to be a little anti-climatic. The machines you indicated are not, basiclly, any different than any other espresso machine. If you do not understand how those machines are the same as all other espresso machines then you will have a hard time understanding how they are different and, arguably, better.

You can think of espresso machines as vaugely like a human body. All humans share the same internal systems. A couch potato and an olympic athelete have pretty much the same make up. If you are really interested in why the super-duper-fancy machines are so much "better" than most others I would start by studying some work horse production machines so that you have a better understanding of the basic systems.

Brady's suggestion of looking at a La Marzocco is great. They've got great documentation online and that will give you a good look into one of the best production units around. You can also find all the documentaion for the Nuova Simonelli machines, including the much lauded Aurellia, at the Nuova Simonelli USA web site. I would start by looking at these two because they cover the two basic machine configurations, heat exchanger and dual boiler. One is not inherently better than the other. Just two ways of getting to the same place.

I would also look online for some general tutorials for how espresso machines work. Those general principles will be directly reflected in any machine you look at, including the Speedster, Slayer, and Hydra. It is in understanding those general principles that will allow you to understand the innovations the designers have built into their fancy machines. Once you start learing about the generalities of espresso machines you can bring back a specific question about the difference between, say, the pre-infusion strategy of the E-61 grouphead units versus how Slayer does it.

I know this isn't quite the info you were looking for but I hope it helps in your quest. Keep going and keep asking questions.

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Permalink Reply by victoria fallon on March 7, 2010 at 6:47pm

Mike and Brady,
Thank You. My goal is to better understand the inner workings and general principles of an espresso machine. Thank you both for the recommendations I will start with the two suggested.

stay tuned for more specific questions.





Mike Sabol said:

Hi Victoria. Those machines are quite beautiful. I can see why you'd choose them to look further into. But your question is actually a pretty broad one so my first answer is going to be a little anti-climatic. The machines you indicated are not, basiclly, any different than any other espresso machine. If you do not understand how those machines are the same as all other espresso machines then you will have a hard time understanding how they are different and, arguably, better.

You can think of espresso machines as vaugely like a human body. All humans share the same internal systems. A couch potato and an olympic athelete have pretty much the same make up. If you are really interested in why the super-duper-fancy machines are so much "better" than most others I would start by studying some work horse production machines so that you have a better understanding of the basic systems.

Brady's suggestion of looking at a La Marzocco is great. They've got great documentation online and that will give you a good look into one of the best production units around. You can also find all the documentaion for the Nuova Simonelli machines, including the much lauded Aurellia, at the Nuova Simonelli USA web site. I would start by looking at these two because they cover the two basic machine configurations, heat exchanger and dual boiler. One is not inherently better than the other. Just two ways of getting to the same place.

I would also look online for some general tutorials for how espresso machines work. Those general principles will be directly reflected in any machine you look at, including the Speedster, Slayer, and Hydra. It is in understanding those general principles that will allow you to understand the innovations the designers have built into their fancy machines. Once you start learing about the generalities of espresso machines you can bring back a specific question about the difference between, say, the pre-infusion strategy of the E-61 grouphead units versus how Slayer does it.

I know this isn't quite the info you were looking for but I hope it helps in your quest. Keep going and keep asking questions.

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Permalink Reply by Brady on March 9, 2010 at 10:36am

One of the more important concepts of espresso machine operation is boiler temperature control. The two most common ways of controlling the temperature of the water in the boiler are mechanical pressurestat and PID thermostat.

A mechanical pressurestat is a mechanical device that contains a membrane and a contactor switch. It is connected to a tube that leads to the top of a boiler (above the water level) in order to "monitor" the pressure of the steam in the boiler. Remember that water in a pressurized vessel (like your machine's boiler) boils at a higher temperature, and that pressure and temperature are directly related. This means that you can figure out the temperature of the water in a pressure vessel if you know the pressure in the system. A pressurestat turns the heater on if the boiler pressure is below a certain threshold (for example, 1.0 bar) and off once it reaches another (higher) pressure (example 1.1 bars). This component makes a noticeable clicking sound when it moves, as it is mechanically making and breaking the switch (contactor).

Pressurestats are a reasonable way of controlling boiler temperature, and are still used on lots of machines. However they are not capable of controlling temperature within the very small temperature range that many of us now demand. They will turn on the heating elements for several seconds - 10-15 seems right for a ballpark. This leads to "overshooting" the target temperature and then cooling below it. It would be like trying to drive your car at 45 MPH by alternatively flooring it until 55MPH, then coasting to 35, then flooring it again. You do average 45MPH, but there are better ways.

PID controllers are relatively new in production espresso machines, though the technology has been around for quite a while. They are basically very good electronic thermostats - reading the water temperature directly. They operate using the idea (greatly simplified here) that the farther away the water temperature is from target, the more heat should be applied. They work by pulsing the heater for shorter and shorter durations as you approach target, thus minimizing overshoot. Its more like tapping your gas pedal very briefly to bump your car up to 45.5 when it slows down to 44. There are other things going on here (read this if you are curious and love math), but that's the basic idea.

Most espresso machines at this point still use some form of pressurestat. PID is used on top-of-the-line machines, and is a more expensive option. Machines can be PID'd using aftermarket kits to improve boiler temperature stability.

Note that there are other factors that effect brew water temperature, not the least of which is boiler configuration... but that's another post.

Hope this helps.

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