Fix My Coffee
How do I dial in grind size?
One rule: change one thing at a time. If the cup is sour, go finer. If it is bitter, go coarser. Two or three clicks, then brew the same coffee again.
Why one variable
If you change grind, dose and temperature together, you will not know which one fixed the cup when it improves — and next time you start from scratch. Moving one variable looks slow, but it is the only way you actually learn the grinder.
How far to move
Two or three clicks on a hand grinder, one step on an electric one. Big jumps overshoot: you go from sour straight to bitter and never see the right setting in between.
Stay on one coffee
Dialling in while switching beans every brew does not work. Work through one bag — and expect the setting to drift slightly as that bag ages anyway.
When to stop
When the cup starts tasting sweet and neither sourness nor bitterness stands out. Write that setting down so you never have to find it again.
Fix My Coffee turns this into a log: it remembers what happened at which click, and keeps the setting that worked as a recipe.