Cafelat Robot Review

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drgary
Team HB

Postby drgary » Sep 29, 2018, 11:22 am

The Cafelat Robot manual lever espresso machine has been eagerly anticipated since Paul Pratt began to reveal it in April of 2016. By then he had been working on it for a year. Anyone who knows about Paul would have high expectations because of his reputation as a premier restorer of espresso machines from the 1950s and 60s. The journey from concept to manufacture can be a long one, even for someone with Paul's skills and his access to manufacturing and fabrication sources. For those who committed to the first batch on Kickstarter, the wait is nearly over, and you won't be disappointed! As someone who appreciates vintage lever machines, I feel extremely fortunate to have a demo version of the Robot sitting on my counter so I can offer first impressions. Soon you will see this review joined by several members of Team HB. Now let's get down to business!

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I'll start by summarizing first impressions and will soon offer more detail and photos.

I'm still dialing it in, but as I write this I just put the Robot to the Nordic roast** test, and it is fully capable. I also just pulled a first-rate shot of a local favorite, Stumptown Hairbender, a darker medium roast that likes to be updosed. Since even darker roasts simply require cooler temperatures, the Robot can pull the full range of espresso roasting styles.

Everything is high precision and well thought out. The parts fit together perfectly. The materials are the best of old school -- stainless steel and aluminum -- and now, silicone. There is no plastic* in the water path. Apparently the Robot is Paul's interpretation and upgrade of the Faemina Baby / Faema Baby, a manual pourover machine that initially appeared as the Mignon Cremacaffe in 1950. The beauty of these ultra-simple pourover machines is you can be quite consistent by using a good grinder, weighing the dose and shot, and using water heated to a target temperature.

I will see a Faema Baby for the first time next weekend, so the way the Robot works is unexpected to me and I'm sure is quite traditional. The piston hangs a little loose in the upper part and can look misaligned because it's on a swivel. The portafilter locks in and seems like it isn't properly seated until you bring the piston down to engage the one-piece 58 mm cylinder and basket, and it aligns itself perfectly, stabilizing the portafilter in the group. The tamper fits it perfectly and is held very nicely in either of the Robot's "hands." The removable two-spouted bottom of the portafilter has a friction gasket of silicone, again, a perfect fit and already tested in his other portafilters. It's also fairly hefty. Since Paul is an accomplished machinist, the tolerances are very fine. Of course the piston, basket and portafilter are stainless steel. Paul has sent two versions of the filter basket for me to try, the Pro basket, designed for fresh coffee from a proper espresso grinder, and the pressurized basket for coffee that is pre-ground for a moka pot and can be obtained at many grocery stores. This is also the Barista version of the Robot, equipped with a removable pressure gauge. In addition to the aluminum version Cafelat is offering the Robot with green or yellow powdercoat.

Paul's overview and instructions can be seen on this Kickstarter page.

* The only plastic content I know of is the set of PTFE washers in the internal lever arm assembly, nowhere near the brew path, and the PTFE tubing that feeds the pressure gauge.

** For newcomers a Nordic roast is very light to highlight coffee's origin flavors. Brewing requires high temperature and a capable grinder.

*** This thread will be closed for comments until I insert more photos and fill in more details.
Gary
LMWDP#308

What I WOULD do for a good cup of coffee!
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drgary
Team HB

Postby drgary » Sep 29, 2018, 6:05 pm

Let's get into more detail, with photos. Here's what came with the review machine, which includes some extra bits, including the pro filter basket and the pressurized basket, plus a Cafelat coffee dosing spoon, an extra gasket for the portafilter bottom, and some Molykote 111 silicone lubricant. The Reward version I have ordered will be equipped with the manometer and will include one type of basket, a shower screen, an extra piston seal and a silicone cup pad for the base. I've ordered the pressurized basket as an add-on for traveling without a grinder.

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The Kickstarter campaign lists the Robot as weighing 2.8 Kg / 6.2 lbs., including the steel tamper. The hands-on experience is of something that is solidly built but not unwieldy. The portafilter with filter basket and shower screen inserted weighs in at over 1 lb. Keep in mind that this is a 58 mm filter basket, not the smaller size we're used to in many home levers.

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The press-on bottom of the Cafelat portafilter is a perfect fit and is secured by a silicone o-ring. This part alone is 173 gm, which is included in the weight above.

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The tamper is held securely in either of the Robot's hands but is not a tight fit, so it's also easy to remove. It's well thought-out from a user's point of view.

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The manometer is small, so it scales well. It has an attractive face.

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Here is how the manometer assembly is fitted to the machine.

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Here are views of the top and bottom of the pro and pressurized portafilters. The pro version is on the right.

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For a sense of scale, here's a comparison of the Robot portafilter on the right, with a 58 mm Conti Prestina portafilter in the middle and a 49 mm Richard Penney Espressme portafilter for an Olympia Express Cremina.

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Gary
LMWDP#308

What I WOULD do for a good cup of coffee!

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drgary
Team HB

Postby drgary » Sep 29, 2018, 6:28 pm

Getting acquainted

I'm just starting to get familiar with the Robot and like it more and more. Here's a feature that surprised me because it looked "off," but there is nothing wrong. The piston appears to be swiveled, but this is part of its self-aligning design.

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Inserting the portafilter into the group involves aligning the tabs with the front and back while keeping the arms raised, so it is clear of the piston when initially loaded.

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Turn it to the right, and it will not be snugly secured the way it would be in a machine like a La Pavoni lever. Again, there's nothing wrong because the piston has not yet engaged the cylinder part of the portafilter basket. Prior to first use Paul recommends lubricating the piston seal with silicone lubricant or hot water. This will help it slide into the cylinder and also makes it easier to remove when the shot is complete. Eventually the lubricant or coffee oils will be sufficient. Once the piston slides into the cylinder, the portafilter is firmly held in the group and everything is correctly aligned for shot-pulling.

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When the shot is complete, the basket may be held in place by the friction hold of the piston gasket. Once you've completed the shot the filter basket isn't very hot and is easily removed by hand. Time will tell if the filter basket comes loose as the piston gasket becomes seasoned.

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Gary
LMWDP#308

What I WOULD do for a good cup of coffee!

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drgary
Team HB

Postby drgary » Sep 29, 2018, 6:42 pm

Starting to dial in

Shots on the Robot can be precisely dialed in. I've just started to experiment with different coffees. Beginning with a darker medium roast, Stumptown Hairbender, I've found a sweet spot at about 18 gm in, 97 C / 206°F water poured in and an unheated filter basket, leaving about 8 mm / 1/3 inch from the top to avoid an initial spill. I pulled the shot all the way through, and it yielded a beautiful, fruity espresso that was rich with crema all the way to the bottom of the shot glass. The grind setting is coarser than I use with my La Pavoni or Olympia Express Cremina. My commercial lever uses a coarser setting than the home levers, and the setting for the Robot is coarser than that. You'll need to find that setting on your grinder. As I've varied shots while dialing in, I've been able to achieve flavor layering equivalent to an Elektra Microcasa a Leva or Conti Prestina.

This morning I pulled a shot of a Nordic-roasted Ethiopian natural from a local roaster with that style. Fellow HB Team member Sam Law has experience with the Faema Baby and advised me to preheat the filter basket and to pour hot water on top of the shower screen, then discard that and pour in hot brew water. I did that using water just off the boil and the temperature was just right. So, if you're used to a very light roast, the Robot is capable of handling it. Sam will be joining this review soon.

This means we have the full range of espresso brewing temperatures available, which is extremely good news.

One of my first tries with the pressurized basket was Pellini Top, an Italian pre-ground coffee blend packed with inert gas and recommended by our expert member, Lucio Del Piccolo, aka LVX. If you don't know Lucio, he's a leading collector and historian of caffetieres, and his blog is here. The coffee itself is sweet, mild, and like dark chocolate, but the grind is very fine. Although I didn't get the mouthfeel I wanted, I hit the temperature about right, starting with water heated to 87° C / 188° F and an unheated filter basket.

I'll continue experimenting with the pressurized basket by grinding coarser as you would for a moka pot, as recommended by Lucio. By the end of the week I'll receive a popular Italian blend that he also suggested as the most popular coffee in Italy, Lavazza Qualita Rossa. It is supposed to be ground for moka pots and contains 30% Robusta, which should augment crema production. Lucio assures me that a good quality Robusta is not to be feared! :?:

Let's not forget the design

I'm going to close out today's post with a beauty shot. Let's keep in mind that the Robot has already won a Red Dot design award. The Faema Baby that inspired it is a minimalist design. I believe the Robot is a whimsical step up from the Faema Baby with its take on the science fiction illustrations of the 1950s. As it sits on my counter I find it beautiful to look at, and comparable to outstanding coffee brewer designs of that era, like this mid-century classic, the Robbiati Atomic coffee maker.

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Gary
LMWDP#308

What I WOULD do for a good cup of coffee!

samuellaw178
Team HB

Postby samuellaw178 » Oct 07, 2018, 6:56 pm

Thanks Gary for the great intro and review!

Since I have more experience with the Faema Baby, which is almost a dead ringer for the Cafelat Robot, a lot of my expectation/comparison will be made based upon that. We will also briefly go through some of the differences and improvements between the two.

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Twins from different eras!

First impressions

When I received the parcel, my immediate reaction was "wow, that's heavier than I expected!" Upon unpacking, the Robot sits reasonably compact on the counter, similar to the Baby. The Robot weighs about 2.4 kg / 5.3 lb(without tamper). For this reason, the Faema Baby almost feels like a toy- the Baby is mostly made of alloy and is much lighter @ 1.3 kg /2.9 lb.

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'I am taller' 'Noooo, I am taller!'

All of the Robot's parts are extremely well-made. If you are someone who appreciates fine details, you will come to be impressed by the impeccable finish on all the stainless parts - including the lever arms, which have some tricky curves for polishing, as well as the portafilter. The workmanship that Paul Pratt is famous for in restoring vintage machines is certainly carried over to these Robots. That alone makes it well worth the price!

Except for the cast aluminium body, almost every part of the Robot is made of stainless steel. This of course includes the accessories such as baskets, portafilter, shower screen, dosing spoon (!), etc. Really impressive.

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Cafelat Robot's accessories on the left (100% stainless steel), Faema Baby's on the right (mostly alloy).

The most critical part - the basket

As mentioned by Gary, the unique characteristic of the Robot is that the basket and the piston's cylinder are a one-piece design (see picture/diagram below). In a classic lever machine, the basket and cylinder are two separate components where the cylinder is the hefty lever group head made of brass and is designed to cool down superheated water from the boiler.

Having this one-piece design provides several advantages for the Faema Baby. For one, there is very little mess when grinding directly into the basket (think of it as a free built-in grind dosing funnel!). Secondly, there is no need to preheat a separate cylinder.

In this one-piece design, getting the basket thickness right is critical as too thick of a basket will result in significant heat loss - causing a low brew temperature or necessitating an extensive preheat routine. Alternatively, too thin of a basket will allow deformation under pressure. The Robot's basket weighs a measly 83 g / 2.9 oz, which is a reasonable feat when you consider that a typical basket weighs around 25-35 g / 0.9-1.2 oz and a typical lever group head (i.e., cylinder) around 3-5 kg / 6-11 lb!

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Left : Comparison of the Robot's two-in-one basket and a conventional basket design (this picture is from Cafelat on the Robot's Kickstarter web page). Right: The working principle of the Cafelat Robot's special basket.

In case you are thinking of getting an aftermarket tamper, please note that the Robot will require a special tamper size. Despite being a '58mm' basket, my regular 58mm tamper (i.e. not the oversized 58.x mm tamper for VST, etc.) did not fit. Measured with a caliper, the tamper that came with the Robot measures about 57.30 mm and the Robot basket diameter around 57.85 mm (which tapers down to about 57.5 mm). However, there is no actual need to obtain an aftermarket tamper - the tamper supplied with the Robot works reasonably well and you get the cool factor where the tamper can be hung onto the Robot when not being used.

Other miscellaneous notes

You may notice a slight metal rubbing sound when moving the lever arms up and down. This is perfectly normal as it is inherent as part of the design - there are some moving parts in the arm mechanism that will slide over each other to allow movement. As the arms are made from stainless steel, wearing out is very unlikely.

A PTFE shim is sandwiched between the flat moving part between the two lever arms to provide smooth lever movement as well as to minimise lever wobble. For some of you observant ones, you may notice there is minor movement in the lever arms - again, it is part of the design requirement to allow for alignment of the piston/portafilter when in use and for ease of assembly. How did I find out? Well, I 'cleverly' tried to shim the arms to fill up the small gap (0.1mm or so), but it was almost impossible to reinstall! Note to self: don't try to reinvent the wheel. :oops:

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Note the white PTFE shim piece that was sandwiched between the two arms.

Parts compatibility with vintage Faema Babies?

One of my questions coming into the review was whether we are finally getting a new spare part source for the vintage Faema Babies. As some of you know, sometimes these old Faema Babies can be found on the secondhand market but often with missing parts such the basket, portafilter, seals etc. Unfortunately, I reluctantly report that most of the parts on the Robot are not cross-compatible with the Baby. This is most likely due to the design improvement implemented on the Robot (different portafilter bayonet system) and also possibly because the Robot was designed around the silicone seal (i.e. , incompatibility was not by intention). The shower screen is the only part that is interchangeable between the Robot and the Baby.

How easy it is to use?

Compared to many other portable devices, the Robot is very straightforward to use. Back-to-back shots can be managed with a reasonably quick turnaround time due to a relatively minimal routine. In my experience, the most 'challenging' part in getting used to on the Robot is when locking in the portafilter. This is where you are required to lift the lever arms with one hand while holding the portafilter (filled with hot water) in another. However, the learning curve was short and I was very comfortable from shot 3 onward.

Brew pressure and pressure gauge - usage impressions

Since I've got the 'Barista' version, it has the pressure gauge fitted to show real-time brew pressure. The pressure gauge is small (and cute), and it is surprisingly very readable. Although the pressure gauge itself is workable, I feel that its placement or the direction of the gauge could be improved. I often lean my body over the Robot and use some of my body weight to help pulling the shot - meaning I will be looking over the Robot from top-down. In this position, it is difficult to look at the gauge during the shot extraction when it matters. Obviously, I could also pull a shot while staying in front of the Robot and facing the gauge. However, in that position, I could only comfortably exert around 5-6 bar as the stainless steel arms can start to painfully pressing into your hands when applying extreme force. Fortunately, I found that even a 5-6 bar shot can be very delicious. In my opinion, adding silicone sleeves around the arms could make them more comfortable to hold. In an email correspondence with Paul, he is currently looking into a new gauge/bracket design that can be swiveled to any position.

With the minor caveat above, the main advantage of the Robot over the Faema Baby is its versatility, with a full range of pressure available (up to 9-11 bar *) and a real-time brew pressure readout. The characteristic of the Robot's shots can be changed by manipulating the brew pressure. With the Faema Baby, I am often limited to 5-7 bar (assuming the mechanical advantage of the levers on both the Robot and the Baby is the same) as I was wary about breaking it (especially the thin basket), resulting shots that tends to taste softer and have lesser crema in comparison to the shots from the Robot.

*Edit 20 Oct 2018 : Cafelat does not recommend going much beyond 8 bar, although you have the ability to do so. Adhering to the guide should ensure you get many years of faithful service out of the Robot.

Preheating - temperature performance

For a pourover/unpowered espresso device, the main challenge is often the heat loss or the ability to reach a reasonable brew temperature. Without any preheating procedure, the brew temperature of the Robot reads about 90 °C / 194 °F by immersing a thermocouple into the hot water above the tamped coffee. This brew temperature can be perfectly acceptable for darker-roasted coffees to minimize potential bitterness. For lighter roasts, you can increase this brew temperature by preheating the portafilter/basket assembly by briefly soaking them in hot water (such as in a latte cup).

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Preheating the portafilter assembly in a latte cup.

Another preheat technique I've learned from using the Faema Baby is the so-called double-pour technique. This is done by filling the portafilter (tamped coffee bed and shower screen in place) with off-boil water and allowing it to sit 5-10 sec. Instead of brewing directly, discard the water and refill the basket with fresh off-boil water. By doing that, a brew temperature of 92-94 °C / 198-201 °F can be achieved easily without any laborious preheat routine.

I was using a medium-light roasted Colombian coffee for some of the test brews - it can taste harsh/acidic when not pulled properly. Using the double-pour technique, the taste seemed about right to my palate. I have also purchased some ultra-light filter roasts for testing (the Kenyan was retailing for AUD$88/kg!) and I was able to get great results with both the light roasts (albeit with minimal crema, not dissimilar to what I get using the commercial lever and Linea Mini).

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Ultra-light filter roasts used for testing the Robot.

This double-pour technique may seem unconventional to some, as it involves discarding some 'coffee water' that is light-brown in color. However, this discarded preheating water proved to contain very little coffee material and therefore the loss was negligible - I couldn't get an accurate reading on my Atago refractometer (<0.05% TDS), representing less than 0.1% loss of the total extracted/soluble coffee solids.

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The discarded preheating water - not enough to matter...note that the refractometer isn't really up to task for accurately measuring such low TDS %.

Initial impression of shot quality

Obviously, it is not possible to judge a machine (especially a manual lever with pressure profiling capacity) only after a short period. However, the shots have generally been very good, and it is very easy to get great shots once the grind is dialed in. The body of the shots generally seems a hair thinner compared to my commercial lever (Brugnetti Aurora), but the flavour layering was really good (comparable or even better). I can taste the sweetness and the nuances of the medium or light roasts coming through easily. Although the recommended dose out-of-the-box was 10-16g, I found that 18g worked best when I was test driving the Robot. To pull a ristretto (for darker roasts for example), I find that it's better to updose to 20-21g instead of grinding finer. However, this may depend on your pull preference and the type of the coffee/roast.

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One of my first few shots - very easy to obtain good shots once the grind is dialed in.

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Another shot from this morning

Thoughts

Throughout the testing period, I have been really impressed with the ease of use of the Cafelat Robot (for an unpowered device) and its build quality. It was built on the Faema Baby design (an excellent design as it is), and Cafelat has incorporated many modern features such as stainless steel construction and a brew pressure gauge to make the Robot practical for daily use. The Robot seems to work best if I just pull the shots by feeling (rather than being extremely meticulous by going with a timer and executing a pressure profile to the nth degree). For this reason, I can see those who enjoy the hands-on nature of levers and typically have a more casual approach towards coffee (go-with-the-flow type and as long as the coffee is delicious) will love it. Overall, I find that the Robot is a well-executed modern iteration of the classic lever experience - the relatively forgiving nature of levers and the charm of engaging with a lever are two aspects of the Robot that I really enjoyed.

p/s: For the next installment of the review, I am hoping to summarize some key points/guides that was helpful to me in using the Robot.
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drgary
Team HB

Postby drgary » Oct 10, 2018, 1:54 am

An Interlude -- Unboxing the Robot

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(The spoon comes with the pressurized basket.)

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Gary
LMWDP#308

What I WOULD do for a good cup of coffee!

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drgary
Team HB

Postby drgary » Oct 10, 2018, 1:59 am

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My kit includes the pressurized basket and the spoon that comes with it — an option for traveling.

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Gary
LMWDP#308

What I WOULD do for a good cup of coffee!

samuellaw178
Team HB

Postby samuellaw178 » Oct 15, 2018, 12:35 am

Since some of the readers of this review will have already purchased a Robot, this part of the review is intended to serve as documentation to provide some dos & don'ts that may help you in getting the most out of the Robot. If you have not already, going over the manual written by Paul first is highly recommended.

A word about brew temperature and preheating

When brewing with the Robot (or any other unpowered espresso device), it is OK to use boiling water - don't worry, you won't burn the coffee! By the time the water has come in contact with the coffee, some of the heat will have already been absorbed by the basket/shower screen.

With no pre-heating, the Robot achieved about 90 °C/194°F in my experience (depending on your ambient temperature and the measurement method). For some darker roasts, this is a perfectly acceptable temperature range. In the past, I had found that using a lower brew temperature can sometimes be surprisingly good, bringing out a different characteristic of the coffee. So keep an open mind, try it without preheating, and see if you like the result.

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This was how I estimated the brew temperature - it is very sensitive and the temperature can jump around a lot!

Attaching the spout

All Robots will come with a detachable spout that you may choose to use or not. Insertion of the spout attachment may be tricky without silicone grease. One tips I discovered (which I later found was also mentioned in the manual) is to wet both the spout attachment and the portafilter with some water prior to inserting the spout. Using a back and forth twisting motion while gently applying some force will also help. This way you don't have to apply the silicone grease if you choose not to.

However, definitely do not try to fit them dry (and without silicone grease) as it could potentially damage the o-ring.

Coffee dosage

On the box, the recommended dose is 10-16g. However, unlike a conventional machine, there are really no hard-and-fast rules for dosing the Robot. I personally prefer results using 16-18 g. Below that, a fine grind is required and a good grinder is highly recommended. You may also updose to 22 g, or even more. Just be careful when the piston is on the downward travel, as there is a chance the piston may press on the shower screen and potentially damage the screen (particularly if the screen is shifted and not located in the center).

For fine-tuning the shots, Jim (another_jim) has a guide to adjust dose and grind by taste that is almost like it was written for the Robot, since the Robot can accommodate such a large range of dosage. This is a highly recommended reading/refresher and a perfect exercise for the Robot Espresso 101: How to Adjust Dose and Grind Setting by Taste

Tamping

With the deep basket, it may require a different technique than with a regular basket/tamper. With the Robot, I personally like to twist the tamper back and forth (to feel whether it's level) while applying some downward force until the coffee compresses. Don't try to tamp too hard as the tamper might be tilted in the process.


Lock-in

Fun fact : Did you know that the portafilter can be locked in both directions, either towards the left or the right? I didn't!

However, it is still best to lock in towards the right as the ears won't be fully engaged in the left position.


How much brew pressure?

As Paul has mentioned in more than a few occasions, the Robot doesn't need to operate at 9 bar to get great results. I have been pulling shots between 5-8 bars and finding the same.

If you have a pressure gauge (Barista Robot), you may be tempted to go to 9 bar (or even higher) as I did initially. After some experimentation, I find that getting an accurate 9 bar pressure is much less critical than applying a smooth force. There should be a reasonable (but not extreme) resistance from the coffee bed itself. If not, adjust the grind -> too easy to push? Grind a tad finer. Too hard to push? Grind coarser.

I typically like to lean over the Robot to apply some downward force comfortably. If you feel strained at all using this technique, that's likely too much pressure!

While the Robot is rather forgiving, I find that I like to keep the brew pressure above 5 bar, otherwise the result is not as good as it can be.


'Proper' way to apply pressure

One of my early mistakes was holding the claw when applying pressure. My thought was by holding the lever arm near its end, I'd have a longer leverage. However, as I found using the Robot that way can cause some discomfort to your palm. The key here is to apply force on the flat bar (just before the 'claw'). If you still find that it is painful, most likely you are applying too much force. Alternatively, you may also add some sleeves to the flat bar for a more comfortable experience - though it likely won't be needed with the right technique.

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This is NOT the way to hold the lever arm

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I have some clear vinyl tubes (that were cut along the length) that I used as a sleeve for the Robot - they blended in rather well there. You probably don't need them if you are applying pressure using the right technique mentioned above.

Draining the excess brew water

I find it extremely helpful to have a dedicated 'drip tray' to catch the excess water. Another tips you may use is to fill the basket with slightly less water so you don't generate that much excess brew water in the first place.

If you are not making a second shot right after, you can leave the drip tray under the portafilter to catch the drip. The gravity will be pulling down on the Robot's arm/piston to get rid of the excess brew water. So you can just leave it and go enjoy the hard-earned shot you have just made. Come back 1-2 minutes later to a dry puck. So one less step without needing you to do anything!

Note: if you are using fine grind (for ristretto for example), you will find that it takes longer to purge the excess water. Using a coarser grind will be faster.

Technique for removing the basket post-brewing

After pulling a shot, you might find that the basket can be stuck onto the piston seal. To avoid this, lift the lever arms, tilt the portafilter forward (or backward) and the basket will come off easily.

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Lift the arm and tilt the portafilter - easy!

Cleaning the basket post-brewing

The coffee puck does knock out in one piece. However, most of the time there will be some coffee retained in the basket. That is normal and is almost inevitable. You can either wash it in the sink, or use a paper towel to clean it if you are making back-to-back shots. For this reason, I find it easiest to use the Robot near a sink and faucet.

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This is typically how the basket looks like after knocking out the puck.

Pressurized Portafilter, yay or nay?

Initially, I did not expect to like the pressurized basket much (it is usually known as a way to make 'espresso' using less than optimal coffee). However, after some tips from Dr Gary, this basket has performed better than what I had expected, especially for some of the lighter roasted coffees that don't work well for espresso. The mouthfeel of the foam obtained using the pressurized portafilter is indeed different from the non-pressurized basket, but it doesn't have to be the same!

Here's a recipe that I use. This is by no means a fully optimized recipe, but so far it has worked wonderfully! The result tasted like a dessert coffee drink with beer foam mouthfeel (with the fruity light roast I have).

(i) Grind slightly coarser than espresso grind. I used a 13g dose.
(ii) Preheat the basket and portafilter once, and fill with boiling water.
(iii) Lock in the portafilter, and place a cup underneath.
(iv) Some liquid may start dripping into the cup. If not, give it a gentle push to kickstart the process.
(v) Wait for 1-1:30 min, it's ok if the coffee keeps dripping,
(vi) Finish with 'espresso' extraction (10-15 sec) by pressing on the lever arms - generating 7-9bar.

What you get is something between filter and espresso. It is more flavorful and concentrated than a filter drink, with the beer-like cream that provides additional texture/mouthfeel. The lingering aftertaste does resemble espresso but the taste balance is closer to filter. I am normally not a filter coffee drinker, but this is REALLY good.

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Lower the lever arms and allow their weight to pull down on the piston. Alternatively, you can also slot in the tamper for additional weight.
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The was the result. Perhaps it was not as photogenic as an espresso, but tasted pretty good!

One note : I always pull a dummy shot using hot water after a shot to keep the pressurized basket clean. This is because there is a chamber within the basket that can't be accessed easily. Not sure if this helps, but there's no harm in keeping coffee parts clean!

Disassembly, should you?

While you may be tempted to disassemble the Robot seeing it is only fastened by some allen keys, I don't recommend doing that unless there is a compelling reason to do so (i.e., diagnosis of a leak or blockage, etc). This is because reassembly may be frustrating and time-consuming for first timers (specifically aligning the lever arms and piston). Disconnecting the quick-connect tubing might make it leak-prone down the road (the connectors can bite into the tubing and leaving marks) and you may be required to replace the tube. If you are really interested in learning how the Robot is put together, Paul has great videos on the Robot's Kickstarter webpage (in the update section #4 for disassembly and #14 for assembly).


My favourite approach to use the Robot?
Obviously there are many ways to use the Robot and there is no one right way. For me, I found the most enjoyment in the Robot by going with the feel. To do that, I fix a dose (18g), get a shot glass (2oz), pull by volume, adjust the grind by the resistance and taste. No timer, no scale. I don't really aim for a particular shot time or shot beverage, although ironically it does help to do that a few times to calibrate yourself.

As the Robot can easily pull over 40-60 g beverage mass, I find that I tend to overdo the volume. While it is not the end of the world (you might even like the result!), I find that I can prevent that by using an appropriate shot glass to prevent myself from overpulling.