Grind Size
MDPublished
Grind size is the main repeatable flow adjustment after dose and yield are fixed.
Role
Grind size changes resistance, contact time, and extraction. Finer grind usually increases resistance and extraction potential, but too fine can create channeling or choking.
Adjustment
Once dose and yield are fixed, grind is the usual first adjustment for flow. If the shot runs too fast and tastes sharp, grind finer. If it runs too slowly and tastes harsh, grind coarser and check puck prep.
Constraint
Changing grind, dose, and yield at the same time makes it difficult to learn what improved the shot.