Lesson 3 · 5 min
Read Grind and Flow Clues
Choose whether to test coarser grind, finer grind, grinder consistency, or another variable first.
Grind is a direction, not a magic number
Grinder settings do not transfer across models. A "12" on one grinder is not the same as a "12" on another.
The useful question is simpler: should your next test go a little coarser, a little finer, or focus on consistency?
Use taste plus flow
- Bitter, dry, slow, muddy, or clogged often points to one small step coarser.
- Sour, thin, fast, or gushing often points to one small step finer.
- Sour and bitter together often points to uneven extraction or grinder consistency.
- Weak but bitter may need ratio or time attention before another grind change.
When consistency is the clue
If your grounds look dusty and chunky at the same time, different pieces brew at different speeds. Fines can become bitter while larger pieces stay sour or weak.
Blade grinders, dirty grinders, worn burrs, and clumpy espresso prep can all make grind direction harder to read.
Make small moves. Keep the dose, water, temperature, and target time steady while you test.
Practice check
A pour over drains slowly and tastes dry at the finish. What is the cleanest first grind test?
Use both the taste clue and the flow clue.
Remember this
Takeaway: Grind advice depends on taste plus flow.
Misconception: Bitter coffee always needs coarser grind.
Tip: Use small grind moves; exact grinder numbers do not transfer.
Short version: Bitter and slow often points coarser; sour and fast often points finer.