Grinding is about producing particles of a consistent size. Everything downstream — extraction, flow rate, taste — depends on how narrow that band of sizes is. A blade grinder does not produce a band at all.
Why blade grinders do not work
A blade grinder is a spinning propeller in a cup. It shatters beans into a mix that runs from fine dust to coarse chunks, and it keeps cutting for as long as you hold the button, so the only control is time. The result is a bed where some particles are over-extracted and some are barely touched, which is why blade-ground coffee tastes simultaneously bitter and weak.
What burrs do differently
Two hardened burrs are held a fixed distance apart. Beans pass between them and are crushed to roughly the size of that gap. Because the gap is fixed, the particles come out in a much narrower range — and crucially, that range is repeatable, so you can return to a setting.
| Flat | Conical | |
|---|---|---|
| Particle distribution | Narrower, more bimodal | Wider, more fines |
| Typical preference | Espresso clarity | Rounder body |
| Cost of a good one | Higher | Lower |
| Alignment sensitivity | High | Lower |
Will it grind for espresso?
Not every burr grinder goes fine enough, and of those that do, not all hold the setting under load. "Burr grinder" on a box is not the same claim as "espresso-capable". Check the espresso range specifically, and look for whether the adjuster is stepped or stepless.
| Burr type | Flat or conical, hardened steel |
|---|---|
| Adjustment | Stepped (repeatable) or stepless (fine control) |
| Espresso range | State it explicitly — do not assume |
| Retention | Low, if you single dose or switch beans |
| Burr life | 500–1200 kg before replacement |
The grind size visualizer shows what a setting produces as a particle distribution, and the burr grinder guide covers the trade-offs in more detail.
Hand grinders are not a compromise
A hand grinder spends its budget on burrs and alignment rather than a motor, so at the same price it is often better aligned than a motorised grinder. The cost is time — 20 to 40 seconds per dose — and effort, which matters most on hard, light-roast espresso. See the hand grinder guide.
Keeping it honest
Purge on change
Grind a few grams and throw them away when you change beans or setting. The first dose out is mostly the previous one.
Brush the chute weekly
Old grounds go stale and taint every following dose.
Mind the static
A drop of water on the beans before grinding cuts the cling dramatically.
Replace the burrs
Burrs dull. When small adjustments stop changing the cup, the steel is the limit, not your technique.
The upgrade order
Grinder first, then scale, then machine. Community advice on espresso setups is remarkably consistent on this point: a good grinder changes everything.
If you are starting from nothing, the beginner’s station guide puts the grinder in context. Once you have one, the dialling-in guide is the next step.