Extraction question - packing the basket

Matthew Hoffman

Is there an optimum distance that the surface of the coffee in the basket should be from the shower screen on an L1? I have often read that it should pass the "nickel test": that is, when a coin the thickness of a US 5-cent piece is place on the surface and the PF locked in and removed, there should be only the slightest indentation in the coffee. But I think that advice is meant for pump machines.

Matt

Dennis B

Matt, as long as you do not crack the puck of coffee when you lock in the portafilter you are good to go. The L1 has slightly lower shower screen so that's why doses at about 16g work the best in double basket since you can lock in portafilter without cracking the puck.

Problem with getting the puck cracked is that it leads to channeling since water will seek path of least resistance and just go through the crack you created when you locked in portafilter and your coffee will not extract...

Matthew Hoffman

Thank you for a helpful explanation of why the puck should not touch the shower screen on insertion. I was wondering, though, whether there is a way of determining the distance from the puck to the top of the basket in order to avoid that calamity. For example, if I knew the distance was x mm, I could mark my tamper at just above that height.

Matt