F.M. wrote:Hmmm. reminds me of a demo I got from a door-to-door vacuum saleperson! They were keen to demonstrate that a "vaccum" does nothing of the sort.
Well anyways- I've been experimenting with dosing down a bit, using the Vivace Vita roast and the single basket as a measuring device. I have to say it hasn't been the magic bullit I had hoped for....
First I tried dosing less, but same grind and packing pressure (20# now?) and short pre-infusion (:03) OK results but no real improvement and not great crema
Then I tried 1/2 step finer grind, again dosing less and
same packing pressure, with a :
10 second pre-infusion, this choked the machine a bit, but things were easy to get moving once I pushed through the initial resistance. Less crema, possibly over-extracted? Crema had that "cracked surface" appearance.
One thing that bothers me about dosing less, is there's
no way to level the grounds before packing.
I'm thinking next I try a coarser grind & full dose? I may be over-extracting regardless of dose, due to grind.
The problem is not with the preinfusion, or the lesser dose, or the finer grind. It's the degree of compaction.
If you're choking the machine, try tamping very lightly. I mean 2-4 pounds -- barely more than the weight of the tamper and light finger pressure. Do not involve the biceps. (If you react to this suggestion as though it were anathema, you have been thoroughly indoctrinated, not informed.

)
The coffee doesn't have to be "level" it has to be
evenly distributed in the basket. You can chop the rim of the basket in a cross-hatch pattern (chop-chop-chop-chop) with the edge of a metal spoon to
settle the grounds.
Also, on the choking early in the pull: when you first start to pull in earnest, are you giving a hard sudden pull down? Don't do that. Ease into the pull. Too much brew pressure can stall the flow.