Tutorials

Coffee brewing tutorials

Sequences, not opinions. These are the routines that make portable espresso repeatable — written so you can follow them once and then stop thinking about them.

Short answer

A repeatable portable shot needs four fixed things and one variable: fixed dose, fixed basket, fixed water volume, fixed preheat routine, and grind as the only adjustment. Set the grind so a 1:2 shot takes 25–32 seconds, then adjust ratio to fix strength. Change one variable per shot, and stop changing things once the cup is good.

Key takeaways

Dial in with dose fixed and grind as your only lever — this alone removes most of the frustration.
The preheat step is not optional on a machine without a boiler; it is worth several degrees of brew temperature.
Taste before you measure. Sour means under-extracted, bitter and dry means over-extracted, both at once usually means channeling.
Clean the basket and chamber at the end of every session, not at the end of the trip.

Tutorial 1 — Dial in a new coffee

Ten minutes, one bag of coffee, and three shots. This is the routine to run before you leave home, not at the campsite.

Fix the dose. 18 g for a double basket. Write it down; this number does not change again.
Start coarse. A grind that is clearly too coarse. The shot will run in 12–15 seconds. That is the point — you are establishing a baseline.
Grind one step finer, repeat. Keep everything else identical. You are looking for the first setting where the shot reaches 25 seconds.
Adjust by ratio. If the timing is right but the cup is weak, extend the ratio toward 1:2.5. If it is harsh, shorten toward 1:1.5.
Record the setting. Grind number, dose, time, yield. Three numbers make tomorrow repeatable.

One variable per shot. Two variables per shot teaches you nothing.

Tutorial 2 — Pull a pneumatic shot

The sequence for a cartridge-driven machine, in order. Total time from cold: about four minutes.

Heat water. 150 ml to just off the boil — 92–96 °C. A flask is easier than a pot in wind.
Preheat. Run 30–50 ml through the empty chamber into your cup. This warms all three thermal masses at once.
Grind and dose. 18 g, ground to the setting you established during dial-in.
Distribute and tamp. Level the bed, then tamp flat. Pressure is less important than flatness.
Load the cartridge. Hand-tight, never tools. Check the seal is seated and clean.
Brew. Start the timer with the first drop. Target 25–32 seconds for 36 g out.
Depressurise, then open. Wait for the relief valve, then remove the basket and knock out the puck.

If the shot goes wrong, finish it anyway. You learn more from a bad shot you can taste than from a shot you aborted at 10 seconds.

Tutorial 3 — Troubleshoot by taste

Symptom	Likely cause	First fix
Sour, thin, watery	Under-extraction	Grind finer
Bitter, drying, ashy	Over-extraction	Grind coarser or lower temperature
Sour and bitter at once	Channeling	Stir grounds, level bed, then coarser
Shot runs in under 15 s	Grind too coarse or dose too low	Grind finer
Shot chokes, barely drips	Grind too fine or dose too high	Grind coarser, dose 17 g
Good shot, weak cup	Ratio too long	Shorten ratio to 1:1.5
Burnt taste, dark roast	Water too hot	Cool to 92 °C

Tutorial 4 — Clean up without a sink

Knock the puck into a sealable bag. Never into the bushes — it is food waste with caffeine in it.
Wipe the basket and the shower screen with a cloth while still warm.
Flush 30 ml of hot water through the chamber.
Dry the seal and the cartridge interface before packing. Moisture there is what corrodes threads.
Deep clean at home every 30–50 shots, and inspect seals monthly.

Questions

Frequently asked

How long should a portable espresso shot take?

25–32 seconds for a 1:2 ratio — about 36 g of liquid from an 18 g dose. Shorter usually means under-extraction and sourness; longer usually means over-extraction and bitterness. Treat the range as a starting point and let taste decide the final setting.

Why does my first shot of the day taste worse than the second?

Because the machine is cold. The first shot pays the thermal cost of heating the chamber, the basket and the puck. A thorough preheat with the first 30–50 ml of water narrows the gap to the point where most people cannot taste it.

How do I stop the puck from sticking or turning to mud?

Use a slightly coarser grind, dose to the basket's rated capacity rather than overfilling, and let the chamber depressurise fully before opening it. A wet, muddy puck usually means too fine a grind or too much water left in the chamber.

What should I do if the shot sprays or sputters?

That is channeling. Stop the shot, stir the grounds before tamping to break up clumps, level the bed, and tamp flat rather than hard. If it persists, go one step coarser — channeling is often a grind that is finer than the machine's flow path can handle.

How often should I deep clean?

Every 30–50 shots with a coffee detergent, more often with dark, oily roasts. Between shots, a hot water flush and a wipe is enough. Seals should be inspected monthly and replaced at the first sign of stiffening or leakage.

Keep reading

The hardware

A machine that keeps its side of the bargain.

Regulated gas holds the pressure. That leaves dose, grind, temperature and ratio — all of them in your hands.

How it works How it works