Lesson 3 of 12 · Before the first shot
Grind size and why it moves
Why grind is your main dial and why it drifts day to day.
Finer grounds slow the water down and extract more; coarser grounds speed it up. Grind is the variable you will touch most.
Coffee changes as it rests, the weather changes, burrs wear. Expect to adjust a step or two every few days.