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.
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 of the 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.
This is NOT the way to hold the lever arm
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 tip 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.
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.
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.
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.
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, 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.