I had initially been looking at the semi-automatics, but figured that a nice automatic with rotary pump could be run as a semi-auto when desired. On an automatic with a start/stop button, is there any reason it can't perform as well as a semi? Although their often more expensive, they seem to offer a choice in how they can be used.

Also, if the lever on a semi-auto performs the same function as start/stop buttons, it appears the lever is more for aesthetics. An LM is automatic, but I don't hear too many complaints about that. Do the hot-shot-pullers view an automatic machine as a bit, well, too automatic, with those extra buttons? I'm developing a respect for the Cimbali Junior, but I admit the levers look nice.

I can't say as I know anything about the functionality of what you're looking at, but I too dig the look of lever machines. Less buttons, more mechanical controls, like the lever action semi auto machines with knobs for steam and hot water. An example beig something like the Anita at ChrisCoffee. She's a beaut' .

Someone wrote that while an automatic machine can pull shots in the same manner as a semi-automatic, using the start/stop button, the results are not as good. But I also think he may have been referring to a vibe pump unit. I like the look of the lever semi-autos, but if i were to go without the lever, then I prefer the automatics.

perc wrote:Someone wrote that while an automatic machine can pull shots in the same manner as a semi-automatic, using the start/stop button, the results are not as good. But I also think he may have been referring to a vibe pump unit.

I used the volumetric dosing as you describe on the Cimbali Junior (see Programming the Volumetric Doser Buttons in the Buyer's Guide to the Cimbali Junior for more details). There is no functional difference for most semi versus automatic comparisons, i.e., it's just a solenoid versus a mechanically controlled valve. But for an E61 type machine, the real difference is the expansion chamber is replaced by a solenoid:

In fact, that's what makes an "E61" an E61, according to the patent. There is indeed a measurable difference, as noted in Pressure profiles, preinfusion and the forgiveness factor:


Comparisons of Expobar Brewtus (E61 "lever type"), Elektra A3 (rotary), and La Valentina (E61 "solenoid type")

I have not done structured blind taste tests comparing two otherwise identical E61 type espresso machines (one solenoid, one lever) to see how much it matters. To my tastes, my own machine is the solenoid type and it performs as well as other true E61s evaluated on this site.

perc wrote:Someone wrote that while an automatic machine can pull shots in the same manner as a semi-automatic, using the start/stop button, the results are not as good. But I also think he may have been referring to a vibe pump unit. I like the look of the lever semi-autos, but if i were to go without the lever, then I prefer the automatics.

You typically get four programmable water doses on an automatic, plus a manual start/stop. There should be no difference in quality compared a semiauto, just the added capability to regulate water volume. If you use automatic dosing, you can (and should) pull the shot early if it blonds. I can't think of any reason why an automatic would pull inferior shots.

E61-type group heads use either levers or (in the case of pushbutton machines) a grouphead solenoid switch. I don't believe vibe vs. rotary pump is an issue, but there may be subtle differences in preinfusion between the two control mechanisms. Levers do make it easier to control preinfusion manually.

FWIW, I replaced a fully automatic Rancilio L7 (single group commercial machine) with a lever-operated Vetrano about a year ago. I've never missed the automatic dosing capabilities of the L7. In a busy commercial environment, however, I would probably opt for an automatic machine.
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John

EDIT: oops, parallel posting. Nice job, Dan!

Good information. The diagrams are helpful. But, I thought that the E61-type group heads were either:
°fully manual with lever
°semi-auto with electronic start/stop button
°semi-auto with lever using solenoid switch
°automatic with electronic volumetric buttons

If a semi-auto has the lever, doesn't the lever activate the solenoid switch? This being essentially the same as a semi with buttons. There aren't mechanics involved in the function of the semi-auto lever that serve other than to trip the solenoid switch, right?

I know I've read this stuff in the Forums, but then I read something else and need clarification.

perc wrote:semi-auto with lever using solenoid switch

A semi-auto with lever presses a microswitch to engage the pump, but there is no solenoid except the one that controls the boiler refill. See Lino's interior schematics of the E61 for a clear picture.

perc wrote:This being essentially the same as a semi with buttons.

Not at all. One has an expansion chamber (true E61 as defined by the patent), one doesn't (E61 grouphead only, what I sometimes call an "E60.5").

I think I understand the differences now. HB's comment on the 'big red button that does nothing' scenario regarding the Elektra A3 had me confused. That lever machine is distinctly different than E61 lever machines. But while lever machines have do have mechanics involved, and those with buttons have electronics, there is little difference in control, other than perhaps slight variation over pre-infusion (with E61). Am I straight on this?

perc wrote:Am I straight on this?

Yes.