Dan,

It's my own fault for having an unclear antecedent to the demonstrative pronoun "This" when I wrote "This is not a feature peculiar to the lever machine". What "This" referred to is the fact that the latter-phase of an extraction of a moderately dosed basket has a "thinner" taste than the early phase extraction. So the discussion has nothing to do with the pressure profile of a lever pull.

I think you do agree that the latter phase of a pump machine's extraction (latter third, latter half, whatever) is thinner in taste than the early phase extraction, and that this taste difference is a feature of espresso extractions in general, and is not particular to lever machines.

Regards
Timo

Round two:



Same taste profiles, the first almost "salty", very creamy, the second what is usually associated with "lever espresso", clear, wide range of flavors. No hint of bitterness or overextraction.

I might add that the photos in both posts are using ~13g (no scale) of THREE-WEEK OLD Cafe D'arte Firenze that has BEEN STORED IN THE FREEZER in the original bag, and opened once or twice daily.

My methods:

1. Turn on the machine
2. Fix the older kid lunch
3. Drop the baby in the snuggly for a burp; hand-grind the coffee in a 40-year-old Deines that has performed wonderfully for five years
4. Prep the cups, etc.
5. Put the baby in the crib, dose, tamp, lock, and pull the shots
6. Grab the camera and snap
7. Drink, change the baby, clean up lunch

I only bore you with the family details to illustrate how simple it is to make great espresso with the Ponte Vecchio.

PC

Kaffee Bitte wrote:The light tamp that timo is refering to is so light that many would not even consider it a tamp. It is simply using the tamper to flatten the puck enough to lock it in.

Precisely

Regards
Timo

P.S. And speaking of precision, Richard (espressme) made me tampers whose pistons are 6mm thick. The coffee is pushed down exactly 6mm.

RapidCoffee wrote:It would be nice to see some evidence supporting this claim [i.e. that a heavily tamped puck can be fractured on the second piston upstroke, whereas a lightly tamped puck is far less susceptible to such fracture]. Quite frankly, I don't buy it. I think several other factors come into play, including dose, preinfusion, and machine-specific flow characteristics.

Quite frankly, the lever machines we're talking about (excluding the Achille) have no "flow characteristics" in the sense you intend: there is no gicleur; the piston cylinder is directly above the basket. You may have to bump some pump-machine facts in your brain, your call whether it's on a FIFO or a LIFO basis, to make some room for some lever-machine facts. A less dense medium is less susceptible to fracture from penetrating forces than a denser medium (of the same stuff). I believe that's simple Physics

Regards
Timo
P.S. Perhaps I should change "dense" to "rigid".

timo888 wrote:Precisely

Regards
Timo

P.S. And speaking of precision, Richard (espressme) made me tampers whose pistons are 6mm thick. The coffee is pushed down exactly 6mm.

Must say that without your advice Timo that I would still be slowly climbing the lever curve mountain. The light tamp has certainly improved my extractions since I read your Initial Impression on the PV Lusso thread.

As to how far my tamp presses the coffee down, your 6mm is very close to my standard as well.

Ken Fox uses a light tamp too. Ken's no I-believe-it-because-I-saw-it-in-a-book kind of guy.
Regards
Timo

Yes I also read all of Ken's posts on this issue. I also use a lighter, though not as light, tamp on the various pump machines I have worked with. I started doing this out of concern for my joint health. Repetative motion injuries are a SERIOUS problem for a barista making hundreds or more drinks per day. It is a nice side benefit that it can produce a beautiful espresso.

timo888 wrote:Dave,
You go out of your way to make it clear that the individual user's tastes and preferences are what prevail in the end, and that there is no one right way to go about pulling a shot on a lever machine:....

But then you go on to describe a "proper" extraction, and your prescription is not nearly as opened-minded as you were just a few sentences earlier; you clearly favor the ristretto over the normale, and the lungo might as well be something they make on another planet:

Not really, I prefaced the entire section with the phrase, 'Having said that, this is how I pull a shot' and that is a proper extraction for me. Your mileage may vary. Another observation over the years, many people are a bit timid when it comes to putting pressure on that lever, so if your shots are not up to what you anticipated, or lack that creamy consistancy, you may want to check your pressure using the old fashioned bathroom scale trick. No different than putting a pressure gauge portafilter on you pumper if you are not happy with your shots.

timo888 wrote: Given that the machine with its small base is "tippy" when you press down on the lever with "at least 30 pounds of pressure", do you think the designers of the machine expected that 30 pounds or greater (i.e. translating to 8 bars or higher) would be the typical pressure the home user would apply to the lever?

Regards
Timo

Don't know, you would have to ask the engineer about that. Why would they put a screw under the drip tray? Do you think the designers intended for water to never get under the water drip tray?

Kaffee Bitte wrote:Must say that without your advice Timo that I would still be slowly climbing the lever curve mountain. The light tamp has certainly improved my extractions since I read your Initial Impression on the PV Lusso thread.

As to how far my tamp presses the coffee down, your 6mm is very close to my standard as well.

I do use a finer grind and light tamp but have to admit it is not that light. I will try it tomorrow on the Gaggia before I head off to church and see what happens.

Just some general notes about the MicroCasa a Leva (MCaL) and Ponte Vecchio Lusso (PVL). Based on the observations noted in this forum I've been in slow incremental steps increasing the fineness of the grind and decreasing the tamp pressure. Still not at timo888's light touch, but getting there. At this point a set amount of headspace above tamped coffee(~8mm for MCal, ~6mm for PVL) has been determining tamp pressure. Have also converted over to a shorter preinfusion (3-4sec) as advocated by some on this forum. Bottomline has been more consistent quality pulls on both machines. With the blend I just finished off the PVL shots seem to be getting even more heavier, sweeter & creamier than with the old grind & #30 tamp. . So much for the consistent &#30 tamp, 8-10 second preinfusion. This journey into the lever world has been two steps forward and then one step backwards. Not sure where I'll end up