Hi Bill,
Yes, I was thinking of domestic and even of semi-commercial machines.

I have never examined a commercial lever firsthand to see how the group is designed. If the group is detached from the boiler, it would be warmed by convection alone, and so the convection-flow would have to be enough to keep the group mass at-temp. I believe there were adjustment screws on the thermosyphon to address this.

If the group is in direct conductive contact with the boiler and heated by conduction, and if the pstat is working correctly, I would expect heat-loss from the group to keep the boiler element on. How cool the group could get would depend on the deadband setting of the pstat. It's conceivable that with a wide deadband, a shot could be pulled just before the element was due to come on again, resulting in an espresso pulled on the cool side.

Regards
Timo

The group is attached directly to the boiler. It's designed just like the groups on the Elektra, Riveria, etc. except much larger, i.e., has a tube running down in to the water in the boiler. I wouldn't think the deadband on the pressurestat would effect the temp of the group much due to the large mass but I could be wrong. I did only pass thermo in college because I was a graduating senior and the prof felt sorry for me. And that was so long ago I've forgotten whatever I didn't know then.

bill wrote:The group is attached directly to the boiler. It's designed just like the groups on the Elektra, Riveria, etc. except much larger, i.e., has a tube running down in to the water in the boiler. I wouldn't think the deadband on the pressurestat would effect the temp of the group much due to the large mass but I could be wrong.

Well, I certainly don't have the kind of detailed knowledge that would let me compute the specific relationships between surface area, mass, and heat-loss to the ambient atmosphere. But if your shots were cool, then the group was losing more heat than it was getting via conduction from the boiler. Radiator effect alone might explain that...or radiator effect in conjunction with a wide deadband that allowed the boiler temperature to drop quite low before the element was turned back on.

Regards
Timo

P.S. I remember some nifty color shots representing the surface temperature of the group bell somewhere here on H-B.com -- made by someone who had a thermography plug-in to some CAD program.

Well.....the PV looks like the winner for me. A 2oz double may not be ideal, but can be done. It also seems to be the only lever I can find with a water tap. Also, after reading everything I can find, I don't hear anyone talk about quality problems. Nice. I just love the simple design also.

Now I need to keep my Pulser limping along while I save my pennies.

Thanks everyone. I can't wait to make the jump from pump to lever.

-Steve

I am not sure how I missed this thread but wanted to toss my opinion in.

I have been eyeing an Achille since it came out, and IMO you can't do better. All the QC problems seem to be either overseas or on reconditioned units where the seller didn't fulfill their promises.

If you can afford one (BTW, WLL always seems to have one on Ebay at around $850) I would say go that direction.

I could be mistaken, but I seem to recall the PV being a spring lever. I learned on a spring (Sama) but quickly decided I didn't care for the lack of control. I went to a lever because I wanted the control of the pull. And side by side, I like the shots from manual better than a spring. From my own taste vs pressure tests, lower pressure (like a spring) generally makes acceptable shots, and certainly better than over pressure (10 bar) shots, but a manual at 9 bar is indeed the best for my tastes.

So there you go - I would suggest going with your first impression and go for the Achille from a reputable dealer that will stand behind it and I don't think you will be sorry.

That is certainly my plan.

I won't rule that out. At that cost I would be tempted to spend a bit more and just get a rotary pour over. Maybe the lever shootout will be done before I need to make a decision.

-Steve

I remember reading the review of the Achille and being a little concerned about plastic parts and some design features of the group. I have not gone back over the thread, but you could do so if you were seriously considering one. With the Achille you are pushing water through the group manually, but not directly from the piston. It is somewhat of a hybrid in that sense.

The Sama (Ponte Vecchio) design has been around for a long time - probably as long as the Pavoni I guess. Its just a brass piston pushing water down a brass cylinder, through a screen, all of the same diameter. I think this makes for fairly laminar flow, and hence even extraction. I find even the Export, which has the group bolted to the boiler (no water tap however), to be far more temperature stable than the Pavoni Pro I have been borrowing. The group seems to dissipate heat better, and it takes longer to overheat.

2-oz shots on the Ponte Vecchio are the upper limit - it likes 1-1.5 oz much better.

I've only used the manual Pavoni for a couple of months, but I have so far not seen great advantage to the manual vs. spring. What one can do more easily with the manual is control pressure during the shot as note above. This can save an over-dosed or too-finely ground shot by speeding the extraction. One can also achieve greater brew pressures, although I'll be interested in seeing how the Lusso does on the bench.

I've found the manual can therefore eek out a little extra crema or possibly save a shot, but thus far I still prefer the spring. In my opinion the spring guides me to towards the grind/dose/tamp that produces the best shot. I certainly get plenty of crema with the PV using good beans - I've posted some videos of shots here before.

I think you'll enjoy any lever you choose - they are really perfect for those early morning quite times, especially paired with a hand grinder.

PC

I just got my replacement Gaggia from wholelattelove, which was a long horror story with a happy ending. The first 'refurbished' was a wreck, the replacement one (tons of emails, calls, and a month later) was beautiful.

Overheating: You flush, it cools down. What makes it a wonderful machine is that it is highly predictable at what it is doing; once you figure things out, there are no surprises.

Not heating: I'm not familiar with the inner process of the machine, but after a long period of inactivity it feels like a bubble of steam builds up where the heat exchange takes place. Flushing the boiler via the steam wand clears this. This is also crucial when the machine first heats up; The machine will run cold unless the false pressure gets relieved.

The weak link seems to be the steam valve; it loves to leak. This could be just the luck of the draw. I'm about to contact WLL to see if they will honor the warranty and exchange just the valve.

I could not see myself spending money on a machine that could not pull shot after shot after shot after shot. This is not a concern with the Gaggia; with it you can fool around for as long as your system can take the caffeine. With the other ones, screw things up a few times and it is game over until the machine has a chance to completely cool down.