One page. Follow it in order. Change one thing at a time.
The only numbers you need to start
For a double shot on a Breville or most home machines:
- Dose: 18g of coffee in the basket
- Yield: 36g of espresso in the cup (a 1:2 ratio)
- Time: 25–30 seconds from when the pump starts
If you hit all three and it tastes good, you are done. If not, read on.
The five steps, in order
1. Weigh the dose
Not a scoop, not a line on the basket. 18g on a scale. Everything downstream depends on this number being the same every time.
2. Break up the clumps
Ground coffee clumps, and a clump is a channel waiting to happen. Stir the bed with a WDT tool in small circles, from the bottom up, for 10–15 seconds. This is the single highest-value ten seconds in the whole process.
3. Level it
Tap the portafilter gently on the mat to settle the bed flat. Do not bang it — that separates fines from coarse particles.
4. Tamp flat
Pressure matters far less than people say. Level matters enormously. A depth-stopped tamper removes the problem entirely: press until the collar stops, every time.
5. Pull it and watch
With a bottomless portafilter you can see the whole thing. Here is how to read it.
Reading your shot
| What you see | What it means | What to change |
|---|---|---|
| Even, honey-coloured stream from the whole basket | Good extraction | Nothing. Drink it. |
| Jets spraying sideways, or one fast stream | Channeling — water found a weak spot | More WDT stirring, flatter tamp. Check the tamp is level before blaming the grind. |
| Runs too fast, under 20 seconds, pale and thin | Grind is too coarse | Go one or two steps finer |
| Drips, over 35 seconds, dark and bitter | Grind is too fine | Go one or two steps coarser |
| Tastes sour and sharp | Under-extracted | Finer grind, or longer shot |
| Tastes bitter and dry | Over-extracted | Coarser grind, or shorter shot |
The rule people break
Change one variable at a time. Grind, dose, or time — one of them, then pull another shot. Changing two at once tells you nothing, and it is why dialling in feels like guesswork.
About the spraying
If you have just switched to a bottomless portafilter and it sprays everywhere: that is normal, and it is not a fault. The spout on your old portafilter was hiding uneven extraction, not preventing it. You are now seeing a problem that was always there. Steps 2 and 4 above are what fix it, and most people have it sorted within a week.
Beans matter more than gear
Coffee more than about a month past its roast date will fight you no matter how good your technique is. If you are struggling and everything above checks out, try fresher beans before buying anything else.
Questions about your specific machine? Email us — Gabriel answers these himself.