here are some things i’ve learned about my rancilio rocky and silvia (and weight scale and tamping). i’ve been using the spouted portafilter at about 16 grams on the finest grind. i have been pulling from about 15 seconds to 20 seconds (occasionally, 25 seconds) trying to achieve 2-3 oz of espresso.

• to prevent screaching, surround the wand with a rag and steam until the light comes back on or water stops running through the wand
• do this again just before you remove the pitcher from the freezer for about 3 seconds until steam escapes evenly
• assuming that i get all the beans out of the hopper and i use a chopstick to clean out all of the grounds from the tunnel between the hopper and the ground coffee container…(this also requires that after the initial grind is completed and the tunnel is cleared, turn the grinder to a more coarse setting and turn it on to “spit” out more grounds)…then…
• if i use 16 grams + 1 bean, i have leftover grounds; for the next cup, i use 15 grams + about 3-4 beans. this is getting closer to using all of the grounds.
• i round the grounds out along the edge and i tamp probably more than 30 lbs. then i tap to settle the grounds and tamp again and spin the tamper.
• there’s a small scratch on the collar of the grouphead; the portafilter inserts just to the right of that scratch mark