How does the 30 sec shot taste? If you are pleased with the result - don't worry what spring lever max pressure is. 10+ bar pressure isn't the holy grail. If you grind finer than your current setting, you will extend shot length which will tone down acidity.
I prefer the taste of shots with higher pressure (10.5). I'd like to experiment with longer PI at this pressure but I cannot do it because PI must be set to at least 2.5 and with that setting the puck starts sweating after 2-3 seconds when I grind to brew in 30-ish seconds.
You are missing the point, I'm not trying to match anyone, I want to keep my current preferred recipe brewing at 10.5 bar but with longer preinfusion at lower pressure. The main design criteria for the machine was to have two springs in the group so that higher brewing pressure could be achieved, but mine doesn't do that unless I keep the PI pressure high as well.
I bow to your superior knowledge! I thought that there was an optimum amount of headroom between the top of the puck and the bottom of the showescreen?
That's not true...the theory is good, but in practice that's not what happens. I was set up at about 1.3 bar and I still managed to get 10 or 10.5 bar and my group was an old group with 6 or 7 years commercial use on it.
I'm not sure when all that got invented...I only know I don't want the screen to touch the puck when I lock it in. That screen also dips down into the PF once it's locked in, so the headspace is not as great as you see.
As I understand it and @DavecUK correct me if I am wrong, achieving the maximum spring bar pressure (around 10.5 bar) requires there to be sufficient resistance in the puck. Pretty sure if you dispense with any PI period, i.e. hit the dry puck with full spring lever pressure, you will achieve higher spring lever bar pressure irrespective of what PI bar pressure you set. Only caveat to the above is the degree of grind used.
How to answer that one...Well, there's a manufacturer who sells Levers that can only be plumbed, and Levers that can only be run from a tank that have a pump....but not both. So the wise owl who made that funny comment might be right...
But what about a Lever like the Vesuvius Evo Leva, it can be, pumped, and it can be plumbed in....all without affecting preinfusion pressures...seems to be the best of both worlds...perhaps it's a Ferrari, it's certainly Italian. That's without even mentioning all the other advanced stuff.
I'm really not. Whether you're trying to match somebody else's numbers or numbers you just want to hit, you can't force a coffee to behave in a specific way. It's not the machine, it's the coffee (or possibly the grinder). Low pressure starts make pucks less resistant to pressure later on (which is why you aren't hitting max pressure). You might be able to achieve a low pressure pre-infusion and a 10.5 bar shot at suitable flow rate to deliver a 2:1 ratio in 30 seconds withe one coffee and grinder/grind setting but not be able to do it with another. If you've been able to achieve this on another machine, are the basket diameter and puck depth the same?
No, the shower screen ????So, the puck screen
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For anyone interested in actual proof… that's on a Londinium. The concept is the same though.
