Olympia Cremina modsby Claudio Santoro, Simone Forgia
Olympia Cremina C67 completely disassembled, render by Thibault Dussex
One of the machines that for decades has had a legendary status is certainly the Olympia Cremina. This machine made in Switzerland has since its early days bewitched and enchanted thousands of lever machine enthusiasts worldwide most likely because of three peculiarities: its capability (with the right conditions) to produce very high-level espressos; astonishing build quality and its spartan look that dismisses anything not considered essential.This latter point might be rather controversial given that it is probably what pushes many users to dream of improvements that sometimes are not that trivial.
The Cremina intended as we commonly know it nowadays is quite different from the first model that actually resembled a La Pavoni Europiccola and was conceived approximately in 1967. Over the years, Olympia from time to time made some updates improving its own product and at the same time even raised the build quality. Among the upgrades performed, a special mention goes to the bigger boiler made out of stainless steel, the frame no longer made of iron but of stainless steel, the brewing grouphead made out of lead-free brass, a manometer to allow the user to control the boiler pressure and some other internal details.
Despite the numerous changes carried out by the factory, as previously said, many coffee and lever machines aficionados from throughout the world have nevertheless applied and shared some upgrades for an easier use of the machine or even improving its performance. This article represents an attempt to collect in one sole document all those mods considered interesting.
Heat-breaker Teflon gasket
One of the most popular mods performed on the classic Cremina '67 but already implemented by the factory on current production models is the addition of a 1,5 / 2mm thick Teflon gasket placed between the grouphead and the boiler. This gasket, reusable even after several maintenance cycles, allows the brewing group head not to directly be in contact with the hot boiler thus allowing a reduced conduction overheating especially when more shots are pulled in a row.
Making this gasket is extremely easy: regular scissors and a belt puncher are all you need to cut out a Teflon sheet shaped as the grouphead flange; overcoming the increase thickness given by the added gasket can be solved using 4 socket screws 1,5 / 2mm longer than the original ones.
Boiler pressure manometer
This is another feature already present on the Cremina currently produced but missing on the C67 model and certainly has a primary diagnostic purpose: having the possibility to check the real boiler pressure and if it differs from the expected one, then there is likely an electrical issue or simply the pressurestat is blocked or uncalibrated.
A side feature of this mod is the possibility to pull shots using different boiler water temperature and pressure: we know that boiler pressure is directly related to the temperature of both water and steam inside. Therefore, by varying the pressure we can experiment how frothing milk and brewed coffee taste change because of this parameter.
The first person that we are aware of that applied this mod to his Cremina ‘67 is Sonny Lowe. In order to make it, Sonny drilled the front panel so it could house a manometer that has been connected to the pressurestat via a flexible pipe and a T shaped adapter. The outcome is a manometer elegantly placed at the lower left side of the panel. It's worth mentioning that in the market there is availability of pressure gauges that also incorporate a thermometer thus directly showing both pressure and temperature.
Anti-vacuum safety valve
Like other mods already discussed, this one is also something already present on the Cremina currently in production and has been intelligently included inside the boiler cap. The vintage Cremina '67, instead, didn’t have an anti-vacuum safety valve and consequently, you can see two different phenomena respectively when switching on and off the machine. When you turn the machine on, there is trapped air inside the boiler that once heated up gives you the false pressure phenomena: when the boiler temperature rises, as a matter of fact, the air volume increases more in respect to the water making the pressurestat "believe" that the water has reached the desired pressure when it has not. It is then necessary to open the steam tap and let some steam and air purge out thus to finally have only water and steam at the desired pressure inside the boiler. The second phenomena is about the lever that rises "autonomously" and this occurs when the machine has been turned off and is cooling down; the generated negative pressure is the cause.
Some enthusiasts have added an anti-vacuum valve in place of the safety valve, others, like Laka Arriz Kol have instead mounted an anti-vacuum valve using the socket located inside the machine just behind the steam faucet; furthermore, for the most demanding people, the drain of the anti-vacuum valve (from which some little drops of water can come out during the heating up process of the machine) can be connected to a flexible pipe that would take any condensation outside the machine (to the drip tray for instance). Others, like ourselves, have simply decided to replace the boiler cap with the one currently in use on the new Cremina which already includes an anti-vacuum safety valve.
Steam wand with a single hole nozzle
Since latte art spread to the domestic environment, more and more Cremina users take on this technique. Frothing milk aiming to produce a texture with the right micro-foam using the 3 or 4 holes tip is not that straightforward. The Cremina '67, among other things, has a stock steam wand with brazed tip, that makes it impossible to replace only the tip. The new Cremina, instead, has a removeable nozzle: this is the reason why many users replaced the whole steam wand with the latest model so to be able to use a single hole tip.
It is common knowledge that Cremina '67s manufactured up to about 1982 had their boilers insulated with asbestos. Anyone who bought a Cremina ‘67 manufactured up to that time will certainly have faced this problem, as asbestos tends to flake off over time and is highly carcinogenic. We therefore strongly recommend the removal of this insulation (possibly by turning to specialised companies) and re-insulation with modern materials that are safe and easily available. The insulation is certainly useful for greater energy savings and at the same time it is also useful for less overheating all the components inside the machine, also lengthening the pause times between the switching on and off of the pressurestat.
Boiler completely cleaned and with new insulation material. Picture by Juan Jiménez
Pressure Profiling Kit and Smart Espresso Profiler
As already explained in the article "La Pavoni mods" in the section on Pressure Profiling Kits (PPK), with the advent of the movement called "Third Wave Coffee" being able to monitor and control the pressure curve during extraction is a feature that has become particularly useful and interesting. At the time of writing this article, there are three kits on the market for Cremina that allow a pressure gauge to be mounted on the grouphead and all are developed and sold by Gábor Laczkó (owner of Naked Portafilter). The first has minimal aesthetic impact and is rather in line with the rest of the machine; the second, called SEP (Smart Espresso Profiler) is digital and aesthetically bulkier but offers additional functionality. In fact, the latter allows the user to record the pressure profile with an app and thus subsequently allow the user to try to imitate this profile or that created by others with the same device, as well as allowing the extraction to be analysed at a later date. Lastly, the third is a hybrid version combining analogue and digital as seen in the picture below.
Hybrid Pressure Profiling Kit with analogue pressure gauge and SEP
In order to be able to perform repeatable extractions, a thermometer with a probe on the grouphead is essential. For a minimal cost, it is possible to purchase an LCD thermometer and, in this way, it will be easy to perform targeted extractions with specific temperatures. On machines such as the Olympia Cremina, the water coming from the boiler is at a much higher temperature than the water needed to brew the coffee, so the final temperature is determined by how much the water cools once it comes into contact with the grouphead. With this modification it will therefore also be possible to easily manage several extractions in a row, just remember that the temperature measured by the thermometer will be that of the group and not of the water itself and should therefore be lower. With a bit of trial and experience, you will then be able to work out at what temperature to keep the brew group to achieve certain results in the cup.
Sight glass light and digital thermometer with hidden probe
When one goes to the kitchen at the first light of dawn in the morning to switch on the Cremina, being able to check the water level in the boiler is not always easy as it is not clearly visible without a good light. To overcome this problem, Sonny Lowe came up with the idea of placing an LED light inside his Cremina '67 to illuminate the sight glass. In this way, even in a totally dark room, the water level is easily readable. What is really ingenious, however, is the realisation of this modification and the subsequent evolution it has had with the addition of an LCD thermometer hidden inside. Let's go into more detail.
Inside the machine Sonny has placed a tiny transformer that takes alternating line current (it works with both 120V and 240V) on the input and returns 12V used to power the LED. The transformer can be connected in two different ways: the first is that it switches on the light when the machine is turned on; the second is that it switches on the light as soon as the plug is inserted into the socket. The evolution of this design was then the addition of an LCD thermometer powered at 12 V by the same transformer supplying power to the LED light and with the probe passed from the inside of the machine to the grouphead unit via the groove around the latter's flange. The interesting thing is that in this way, the aesthetics of the machine are not affected in the slightest as there are no wires dangling around the unit but all the work is done discreetly “behind the scenes” without even needing batteries any more. In order to achieve this, both the wire and the thermometer probe used are very thin so that they pass through a very narrow slot and the application of the probe on the group head takes place in a small, hidden spot.
Sight glass light kit with digital thermometer
Pressurestat with adjustment screw on top
We first saw this modification in an old post on the Londinium blog and it involves repositioning the new generation pressurestat now found on many Creminas with the adjustment screw facing upwards instead of sideways. This modification can also be applied to older models if the pressurestat is replaced with a modern one, and the advantages of repositioning will be mainly two:
the first is that by placing it with the adjustment screw facing upwards, in order to change the operating pressure of the boiler it will be sufficient to unscrew the bolt under the boiler cap, then remove the cover on the top of the machine and using a screwdriver it will then be possible to easily act on the adjustment screw without having to remove the side panels;
the second is that in this way, it will be more unlikely that limescale deposits will clog the pressurestat if you have very hard water and do not descale frequently.
To implement this modification, a U-shaped fitting is required to connect the pressurestat and slightly longer, heat-resistant electrical cables.
Drip tray with integrated scale
For people who like to experiment, it is certainly useful to be able to know and monitor parameters such as the grams of coffee used, pre-infusion time, extraction duration and total grams of beverage output. To this end, so-called “smart” scales, such as the well-known Acaia Lunar among enthusiasts, have become very popular in recent years. Following what has been done for many years for the Marzocco Linea Mini, we asked BPlus (thanks to Martin Boleš for designing it) if it would be possible to consider making a perforated drip tray that would allow an Acaia Lunar to be inserted into it. By having a scale always available under the grouphead, it then becomes possible to monitor all the above-mentioned aspects without reducing the height space between the drip tray and portafilter, which becomes even less if using the ones with one or two spouts. Furthermore, this integration means that there is one less object on the kitchen worktop.
Olympia Cremina drip tray grid modified to fit a smart scale
Nylon shims for the lever fork
Especially on some very old machines, it can happen that there is excessive lateral play in the lever fork; nothing that prevents the machine from working properly, but certainly something that makes its use less pleasant. In this regard, several users have remedied this problem by using nylon washers (so as not to scratch any metal-chrome parts) to be inserted in the pin connected to the fork. These washers are available in different sizes and, with some sandpaper, it is also easy to thin them to size.
In addition to modifications aimed at making or improving functionality, some users decide to modify their vintage or even new Cremina from a purely aesthetic point of view. These machines become, to all intents and purposes, unique pieces of furniture accessories that perhaps match the rest of the decor around them. Some replace the Bakelite-plastic handles with specimens made of turned wood or recycled materials obtained, for example, from skateboard boards; others replace the plastic power cable with fabric-covered electric cables in different colours; others paint the metal parts in sophisticated colours and sometimes even change the colour of the originally chrome-plated parts. Finally, there are those who also "simply" enjoy experimenting with various combinations of colors, materials and textures with computer-made renders; some examples can be seen below.
As we have been able to observe, there are quite a few customisations / modifications made to this machine. Certainly not all of them are necessary or recommended, and some, such as the sight glass light with hidden thermometer probe, are even real projects that are still being perfected, but surely a lot also depends on what the user wants. For example, a true enthusiast of the world of coffee and all its technicalities will not be able to do without installing a thermometer or even a kit to monitor pressure, while those who are more focused on experience might lean more towards aesthetic or material modifications such as replacing exemplary wooden handles. In conclusion, anyone wishing to make modifications to their machine must certainly first understand what their priorities and needs are, otherwise they would risk spending time and resources without gaining any real advantages.
Now we ask you; have you already made any of the above discussed modifications? Or do you have other mods to suggest that we have not mentioned? Let us know in the comments, we would love to hear your opinions!