The numbers on your Z1 dial are the gap between the burrs in microns (µm), not the particle size. Use these as starting points and adjust by taste.
| Brew method | Burr gap range | Typical starting area |
|---|---|---|
| Turkish | 25 to 100µm | |
| Espresso | 50 to 300µm | 200µm |
| Filter | 300 to 800µm | |
| Pour over | 400 to 1000µm | 625µm |
| Cold brew | 700 to 1400µm |
Dialing in by taste
Too bitter: grind coarser, shorten extraction, lower water temperature, check the roast date.
Too sour: grind finer, lengthen extraction, raise water temperature.
Espresso runs long (over 30 to 35 seconds for a double): grind coarser, tamp lighter, or dose less.
Espresso runs short (under 20 to 25 seconds): grind finer, tamp firmer, or dose more. Change one thing at a time.
Retention
Anything under 0.3g is normal and within industry standard.
Tap the funnel. After grinding, with the grinder still on, tap the top of the open funnel with your palm 2 to 3 times.
Use the chute. If needed, tilt the one piece chute toward you 45 to 60 degrees and let go. The magnets snap it back and release grounds.
RDT. Add 1 to 2 sprays of water to your beans in the dosing cup, cover, and shake gently before pouring into the funnel. It helps most in dry climates and winter. Too much water can make grounds stick, so start with one spray.
Keep it clean. Oils and fines build up over time and increase retention.
Slow Feed auger owners: a bean or two can stay behind at the end. Pulse the grinder on and off with a couple of light taps on the funnel.
HU burr owners: new HU burrs can clog while they season. See Troubleshooting: HU Burrs Clogging While They Season (Z1).
If you measure more than 0.3g (retention per dose), email info@zerno.co with photos of your workflow and grind chamber.