Wednesday, May 13, 2009

Barista's monologue

We had come to the sad realization that our trusty old espresso machine was probably on its last legs. Steam was continuously leaking out of the frothing nozzle and thus required manual acrobatics to maneuver around the machine to make a cup a coffee without second degree burns. You see I have had this machine for twenty-two years and letting go would be hard!

I already tried once to fix the steam valve, but the internal washer was rock hard and incompetent. I had begun to look online for new machines but was discouraged at the exorbitant prices. It just so happened that I was relating my distress to my brother in L.A. who said that he had just recently made some repairs on his machine with great results.

A dream is born! As soon as I got off the phone with him I began to search the internet for information on my particular make and model of espresso machine. It’s an Olympia Cremina 67, manual pull machine made by an Italian company whose factory is on the Swiss side of the Italian – Swiss border. I began to find info – tons of info on all sorts of machines. And then I hit the mother lode. I found a blog where a guy detailed the rebuilding of the exact same machine that I had. One other interesting tidbit. The general wisdom is that the gaskets in the machine should probably be replaced every two to three years. I guess that 22 years was just a little beyond the usual gasket life expectancy.

First things first. I had to order a complete gasket set from the company. When I called, I was prepared to conduct the conversation in Italian. However, the person answered first in Italian, then repeated the greeting in French and again in German. I figured what the hay, he might speak English too. Sure enough! I asked a few questions and then made my order. This was in September 2008. The gasket set arrived in about 4 weeks, but I felt that I should wait until I had a solid chunk of time to devote to the project.

Blow up diagram of the internal parts of the machine:

Well, first we were away on a trip. Then Thanksgiving was coming and I didn’t want to be without an espresso machine even if it was half broken. Of course Christmas was next and getting ready for the Christmas music program at our church. In January the band had to get ready to perform at two ExL sessions at church. Finally, February arrives and I start.

This machine is so well thought out that disassembling it was fun and gave me a great appreciation for its design and manufacture.

Here’s the wiring to the switches before disassembly.


The wires attached to the boiler



The pressure regulator




The grouphead after removing the dispersion screen, that’s the piston in the middle





View of the boiler after the site tube was removed



The inside of the boiler had some mineral scaling, but not that bad all things and 22 years considered.




This is the bottom of the boiler


View looking up to the top of the boiler




Ok so after some trial and error, here’s the tool that did the trick to clean out the boiler:



And here’s how it looks after cleaning:




The next task was the heating element. This needed some serious work:


I started with the wire brush on the drill, but had to finish using dental picks to get into the small places and clean out the scaling. It gave me a new appreciation for the job my dental hygienist does.



This is a pic of my picks:





And here is the finished product:






Ok, now to clean the grouphead and the piston and replace the gaskets.
Here’s another shot of the grouphead after the larger gasket and piston have been removed:




That little ring in the center with 4 holes is a retaining washer and it held in place by a circlip. The rubber washer is behind it.
I had to remove the hardened washer with a dental pick being carefull not to damage the side walls of the cylinder, otherwise the piston would not seal along the sidewalls.



Here’s how it looked after cleaning and replacement of parts:





Cleaning and replacement of the gaskets on the piston head – the dental pick was again the tool of choice:



It was time to start reassembly. I reviewed the parts and realized that I was missing two crucial gaskets used to seal the glass site tube to the brass housing.
I called Olympia Express in Switzerland at 1:00 AM our time which is 10 AM their time. The woman who answered was very accommodating and apologized for the omission and said she would send out the missing gaskets. I didn’t push her for a time estimate because I know that they are not as intense as we Americans are about being timely. The gaskets arrived in about 3 weeks, and they also sent a second full gasket replacement set. Now I’m all set for the next time I do a rebuild – that should be, uh let’s see, in 2031 if this one lasts just as long!

With things on hold for the gaskets, I got busy with other things and the parts just sat in the garage. Other projects kept taking priority. We had become used to making our coffee in the morning with the 4 cup Moka Express coffee pot on the stove:



A couple of months passed and then I found some time to get back to it. Everything went together pretty smoothly:



In this shot you can see the new rubber gasket protruding from the bottom of the boiler where the heating element is bolted:


To test and adjust the boiler pressure shut-off switch I purchased a pressure gauge at my local Ace Hardware and connected it to the port for the steam froth valve:




Here’s a close up of the gauge:


The recommended pressure is 0.8 to 1.0 bar, that means that the heating element turns on when the pressure drops below 0.8 bar and shuts off when it hits 1.0 bar. As you can see, this gauge is not exactly zeroed, so I had to fudge it a little. For those of you who don’t remember your physics, 1.0 BAR = 14.50 PSI = 1.01972 kg/cm2 = 0.9869 ATM = 750.062 Torr= 750.062 mmHg. OK, OK, I had to look it up too. It was a little too far back on the hard disk and there seemed to be some corrupted files that had to be error corrected – that means dusting it off.

Here’s the pressure switch:


The pressure is adjusted by turning the ridged dial, which I marked so that I could see how far I moved it.

So I finished putting it back together, cleaned all the surfaces so that they’re nice and shiny, and then I ceremoniously put the Cremina back in its place of honor. It was like goin’ home:


Now that all the gaskets and washers seal properly we have to relearn how to make the espresso so that it has that perfect crema on top – hazelnut colored with darker swirls.
Ahhhhhhhh. Time to relax and have a few doppios with a biscotto.

Friday, May 8, 2009

More Landscape Photos!



The Prickly Pear are fully loaded for fruits this year. These particular species are called "Indian Fig" or, in italian, "Fichi di India". In fact, in Sicily (whose climate is quite similar to Tucson), they farm prickly pear fruit for various culinary uses...I am starting to plan ahead and pulling recipes for granita di fichi di india
"Teddy Bear" sunflower







Here are our grape bunches just after the flowers have 'shattered'...Rob spent the day trimming excess bunches and thinning the fruit from individual bunches in hopes that the fruit will grow bigger and juicier and more flavorful! Another trick is to 'girdle' the vines. That is a technique wherein you cut away the outer 'bark' of a vine circumferentially just before the fruit. It is supposed to limit the amount of nutrients that return from the fruit to the vine while retaining the nutrients that the come to the bunch from the vine. Sort of like the human venous system! (Rob is trying that technique on just a couple of the vines!)