by gscace on Tue Nov 06, 2007 5:10 pm
Alright, I've left Dan twirling in the breeze long enuff. As he says, I've got the diminutive two-group Lusso cowering in my basement on a counter across from monstrous 2-grp Marzocco, it's attendant electronix, the Robur and Super Jolly. It's cowering 'cause by comparison the Zocco is towering. The Lusso is Little! You could easily fit the Lusso on the cup warmer of the Marzocco. I guess all of these machines are little and i dunno why.
Before I get too far into this, I'm gonna straighten something out already. I don't worship flat line temperature, OK? What I want to see out of espresso machines is consistency. Ya shouldn't have to twirl around three times anti-clockwise and kill a chicken when you pull a shot in order to get the same result time after time. For your 2600 dollars, or whatever your wife doesn't know you paid for your precious hunk of metal, you should be able to walk up to it whenever you desire a fix, lock and load baybee, push the button or manipulate the thingy or whatever the hell, and the same high-quality liquid beverage should spew forth every time in all conditions of use. Why should it be so hard for cryin out loud? It ain't rocket science. An espresso machine ain't no more than a stupid hot water pump and a steam generator. Once we have capability for consistency, we can talk about more interesting things, like coffee varieties, crops, roasting, and taste. Yah! TASTE, Dammit! TASTE!
Since I'm a consistency nazi, it's of course natural for Dan to ask me to help test lever machines. It's natural because I'm interested in hot water pumps and how the method of hot water pumping influences taste. In the case of lever machines, the pressure of the hot water is variable, declining as the spring-generated force acting on the piston relaxes, in the case of lever machines like the Lusso.
Watchoo get:
The Lusso arrived double boxed from our benevolent sponsor, First Line Ekwipment. It arrived intact, which makes testing and evaluation a lot easier. Included with the miniature machine were two miniature portafilters, two microscopic single baskets and two less-microscopic double basket, which I'm told holds around 13 grams of coffee each. The double basket is straight-sided, with no groove for the retaining spring. That's not a problem because the retaining spring doesn't contact the brew basket anyway. This feature facilitates dropping spent coffee cakes on the floor, and makes fumbling around much easier. Italian Export Control or some government agency over there included the required plastic double ended tamper that fits nothing. They also include a coffee scoop, in case you feel compelled to scoop your freshly ground coffee into the brew basket. The included manual provides reasonable instructions for filling the machine with water and turning it on.
First impressions:
The Lusso continues in the Italian espresso machine architectural tradition of clunky, chunky blocks of metal that look like they came out of a World War 2 submarine or something. It's simple, functional, and very basic. Exposed group parts are hot and they emit steam and hot water when you pull the lever - fun for adults and just the thing for small children. I like it, actually. It's quite retro. The groups are bolted to a chrome-plated bronze plate which contains the water passageways from the boiler. The plumbing layout to the plate promotes free convection from the boiler, resulting in active heating of the groups. Cocking the lever lifts a sealed piston, increasing the volume of a cylindrical chamber above the dispersion screen / block, which is immediately above the coffee cake. When the piston is sufficiently raised, water enters the chamber. When the lever is released, the spring-loaded piston forces water through the cake. As I mentioned before, the water pressure declines as the spring is relaxed.
In keeping with the industrial revolution theme, the Lusso comes with non-articulating steam and hot water wands. They are basic as hell but they work well enough. I quickly learned to just tilt the pitcher to get the milk to roll properly, but if I owned this machine I would prolly tweak the steam wand so that it didn't point straight down. Valves seem very old-fashioned. I'm told that they are typical of machines at this price point ($1100.00). They work fine, but the valve bodies are brazed directly into the boiler. At operating temperature the valve bodies are too hot to touch. I don't think I'm allowed to disassemble a valve to investigate the seal materials, but my engineering judgement (yeah, I have expertise here) tells me that heat conduction from the boiler isn't gonna enhance seal life. Rebuilding the valves looks possible and reasonable, but it'll suck if a valve body requires replacement for any reason. Descaling a valve will also be more of a pain in the yass than would be the case if the valves were completely demountable as ya can't just throw the valve in a bucket of ScaleKleen. The hot water valve on the test machine dripped when I first started the machine up. It doesn't drip now, and the machine is in fact turned on. The included knobs that actuate the valves are tiny round knurled things that are small and hard to use. I suspect that any number of retro-looking espresso machines that use these valve, so I don't see why some of the more zoomy star-shaped handles couldn't be supplied. They'd look and work better.
According to 1st Line's website, the boiler is 3 liters big. In practice it's big enuff to make 10 or so double espressos complete with screen clearing flushes and some steaming before having to refill. So the Lusso is capable of handling a small dinner party. Refilling is accomplished by turning off the machine, venting the steam, removing the fill cap and pouring water into the boiler through the supplied plastic funnel. You won't be catering with this thing. The water level within the boiler is visible through a sight glass. Low water trips a resettable breaker in order to protect the 1kW heating element. Boiler pressure is measured by a mechanical pressure gauge. Pressure is controlled by a small pressurestat mounted on the end of the boiler. The deadband is quite small - around 0.1 bar. As delivered the setpoint is 1.6 bar. Adjustment of the pressurestat requires removing the rear cover of the machine. This is somewhat of a pain in the yass since one must remove the knobs from both the steam and hot water valve, and remove screws on the bottom of the machine. It's not intuitively obvious the first time you do it. Once removed, the pressurestat is easily adjusted. If this were my personal machine I'd immediately put a hole in the case so that I could get to the damn thing.
The drain tray is small and shallow. You don't really need much of a drain tray since you're not supposed to have to perform big flushes. Ya just need to clear grinds from the shower screen. My personal practice is to clear shower screens into a frothing pitcher regardless of how big the drain tray is. I even do this with my Marzocco because it's neater than blurshing that coffee bongwater all over the nether bits. The Lusso's tray is considerably smaller in surface area than the grate. Intuitively you'd think that the tray oughtta approximate the same length and width dimensions as the hole below the grate. So far it hasn't been a show-stopper so I'm goin' with the flow.
Using the machine / making coffee:
Buy yerself a dollar cigar if you got that I think the Lusso is a quaint, anachronism. It certainly is an industrial revolutionary appliance. The salient question is "Can it make decent espresso coffee?" The answer is "Yes. Now go back to work before your boss catches you screwing off." OK, the answer is really more complex. I mean, it's still yes, and for all I know you ARE screwing off at your job, but the issues that get in your face when using this machine are questions of espresso definition and preference. The espresso made with a modern machine using a 58mm portafilter and 18+ grams of coffee is not the espresso made by the Lusso. It's a similar, but different.
I'm gonna first discuss using the machine. As you prolly know already, I'm supposed to build a thermofilter for this machine and its 1-group relative, as part of the smacking down process. That means I need a crotchless portafilter, so I immediately whacked the bottom off'n one. This turned out to be a very smart thing to do, because I could observe the effects of varying my extraction technique.
And now, a few words about my introductory lever actuations. The brewing process is pretty flexible, which you prolly already know if you fool with lever machines. You get to control the piston rise, chamber filling, coffee pre-infusion, pressure rampup (through release of the lever), etc. The starting point I used was to lock the pf into the group, lower the lever (cock the spring), let water enter the chamber and pre-infuse the coffee until drops formed on the bottom of the basket, then brew sweet honey into the portafilter. Well maybe not because my starting point was a bit over-simplified. Turns out that when you cock the lever, you also raise the piston, and air fills the volume. That air filters through the cake, so you have to cock relatively slowly in order not to disturb the coffee distribution. Alternatively you can cock the lever most of the way, stopping before you open the floodgate of water, lock the pf into place, then finish cocking, opening the floodgate. It's easy enuff to do, so I use this method.
For me, long pre-infusions didn't work well. I got better taste and a more uniform extraction cone (bottomless portafilter, remember?) when I pre-infused for shorter periods, only a couple of seconds-worth. FWIW I also concluded that long pre-infusions resulted in less shot clarity when I was doing pressure-profiling tests with my Marzocco. My current technique is to pre-infuse at chamber pressure (also boiler pressure) for a couple of seconds, then release the lever.
The piston displacement of the Lusso's lever group is pretty small. I don't know how small it is compared to other lever machines aimed at the home market, but it's certainly small compared to lever machines that use 58mm portafilters, such as Simonelli's. In fact, the displacement is too small to pull a double shot with one pull of the lever, and prolly too small to even pull a single if one pre-infuses using my pre-infusion preference. I should mention here that Lusso shots are very small compared to shots produced using 18 gm of coffee in a 58mm portafilter. Once you get that thru your thick skull you can go about the business of making nice shots. You have to resign yourself to recocking the lever if you want a ¾ to 1 ounce drink. Since the Lusso is a manual machine you get to choose when you want to recock. Visual and taste clues from the bottomless pf and my taste buds helped beat the idea into my brain that I was in charge of when the recocking took place, and how much extraction was desired. As I mentioned previously, recocking the lever means that the volume of the chamber increases and air comes from somewhere. The wet coffee cake is easily disturbed during recocking. Visual clues that the cake was disturbed come when the lever is released and the extraction stream becomes disorderly, thin, and sprays all over the place. Recocking early, before the piston has traveled its full displacement seems to help for whatever reason. The extractions are more viscous, and much more orderly. Shots pulled in this manner have more body than shots of similar volume that were pulled with lever recock taking place later in the extraction. Reducing headspace above the coffee also seems to help keep the cake under control. Updosing seems to help with this machine.
This is probably as good a time as any to say that I just don't get why the piston displacement is so small. It's very apparent to me when using a bottomless portafilter that recocking the lever plays hell with the extraction. The art practiced here is in figuring out how to mitigate the problems resulting from the recock, and make the best of what I view as a design flaw. Maybe all of the home machines share similar miniaturization, but it would seem to me that lever groups should be designed to produce an excess of water volume, with the idea that the barista would remove the cup from the flow of coffee when the extraction was deemed complete, allowing the post-extraction effluent to drain into the tray.
Group flushing:
The Lusso has a thermosyphon loop, so the group is actively heated. I do a short flush into an espresso cup when brewing the first shot in a series. My thinking here is that in absence of hard data it's prolly a reasonable idea to just make sure the dispersion screen / block are up to temp. I clear the dispersion screen between shots by admitting some water / steam from the boiler into the group. Total volume of the screen clearing flush is around an ounce or so - not much. I've turned down the pressure-stat to 1.2 bars from the factory setting of 1.6.
Steaming:
The fact that the Lusso has a 3 liter boiler means that it has a nice big reservoir of available heat with which to produce steam, despite the fact that the heating element power is only 1kW. FWIW, it takes around 2 kW to provide continuous steam without dropping boiler temperature. As I expected, the Lusso is a prodigious steamer, particularly at the factory boiler pressure setpoint of 1.6 bars. I ended up resetting the pressurestat to 1.2 bars based on my tastebuds' preferences, which resulted in somewhat diminished steam performance, but it's still very good. The wand is easy to use. I made excellent milk on my first try. Since the wand does not move, one must tilt the pitcher in order to induce swirling and one is limited to pitchers of around 20 oz volume or less.
Coffee taste:
So far, I've used two different coffees in the machine. I've brewed espresso using Ethiopian Harrar Horse, lot 14659 (I think that's right) bought from Sweet Maria's, and I've used a Brazilian natural bourbon, whose pedigree I can't remember off hand. Both of these coffees have interesting attributes. The Harrar has subtle taste of berries, good fruit, chocolate, and syrupy body typical of dry-processed Ethiopian coffee. The Brazil has pronounced nuttiness and chocolate.
With the Lusso, when I do things right I produce espresso with very creamy texture and pronounced sweetness. I bet you could produce drinkable espresso using coffees so bright that they would make your brain pucker if brewed with a 58mm portafilter equipped pump machine. What I don't get is the taste clarity that I get with my Marzocco. I know someone's already brought up the red herring that taste comparisons aren't valid, but I say why not? It's not like I'm gonna pick winners or losers here. I'm interested in differences, and I'm well equipped to make such comparisons. When brewed in the Marzocco both coffees demonstrate clear taste notes that do not come through when brewed in the Lusso. That is not to say that the coffee from the Lusso is crap. It's just different. So why is that? There are a bunch of possible reasons, of course. The 'Zocco pf is 58 mm, the dose is 40% more, and the shot volume is a lot higher. The Lusso's pf is 45mm in diameter and the basket is deep. I will probably switch to smaller baskets with the 'Zocco to put the machines on more equal footing volume-wise, although I don't think I can duplicate the Lusso's deep basket. Pre-infusion is somewhat different right now between the two machines, but it's tuneable in the 'Zocco so I could see if I can replicate the Lusso. I suspect that a lot of the taste difference between the two is related to the required lever recocking. It's even possible to mimic this with the Marzocco and I may just do that.
Preliminary conclusions (that just sounds weird) and call for discussion:
I've learned how to pull shots on the Lusso and I've evolved a technique that seems to work. Lever experts feel free to chime in with suggestions.
I find the design to be basic in nature, quite functional, but quirky in some key areas. In particular I question the size of the piston displacement and I'm not wild about brazing valve bodies directly to the boiler, but maybe it's ok. Since it's my first lever machine experience I don't have lots of experience wrt coffee taste compared to other lever offerings aimed at the home market. I find the coffee taste to be creamy and sweet. These attributes are at the expense of flavor clarity.
The Lusso is a fun, modern antique. So far, I'm glad it's in my basement.
-Greg
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