Espresso Puck Prep: Distribution, WDT and Tamping
What finally prompted me was an Instagram video of someone tamping their coffee in mid-air. Portafilter in one hand, tamper in the other, with nothing underneath to press against.
I’ve done it myself. But watching someone else do it made me think: why are we making this harder than it needs to be?
It also reminded me of working at Coffee at 33. I’d sometimes be getting frustrated with my espresso, with shots channelling or just not pouring how I wanted them to. Taras, one of the owners, would come over and make a coffee without changing any settings. A few taps of the basket, a tamp, and somehow his shot would pour better than mine.
Same coffee. Same grinder. Same machine. Which was quite annoying, really.
That stayed with me. As far as I could see, we were both putting coffee into a basket and pressing it down. How could he possibly be doing that so much better than me?
But there was clearly a skill there that I hadn’t developed yet. The way he settled and distributed the grounds before tamping was making a difference, even if I couldn’t explain exactly what he was doing differently.
I think about that now when I’m working on our espresso routine. It’s easy to focus on grinder settings and recipes, but what you do with the coffee before you start brewing deserves just as much attention.
So here’s where I’m currently at with espresso puck preparation. Some of this will probably change as I experiment and make more coffee. But this is the approach that’s working for us in the café, and most of it translates very easily to making espresso at home.
What is espresso puck prep?
Start with a clean, dry basket
Before worrying about distribution tools, get the basket clean.
We knock out the used coffee and wipe the basket with a clean, dry tea towel. I’ve tried little brushes, but I’ve always found a cloth does a better job of removing the grounds and wiping the inside properly. We use a dedicated cloth, change it daily and replace it sooner if it gets damp or dirty.
If you rinse your portafilter between shots, dry the basket thoroughly before adding more coffee.
We’ve noticed shots behave differently when a basket has been rinsed but hasn’t quite dried. I’m not going to pretend I’ve pinned down exactly what’s happening there, but starting clean and dry removes another variable.
And old coffee residue isn’t something I particularly want in the next drink.
Choose your dose and keep it consistent
At Bond Street, we currently use 15g of coffee in 15g baskets.
There’s some flexibility around basket capacity. Different coffees take up different amounts of space, and the weight printed on the basket is a useful starting point rather than an absolute rule.
But we serve three single origin espressos and a decaf. Having the same dose across all four makes life much easier for everyone behind the bar.
It gives us one less thing to think about when switching between coffees or working out why a shot has changed.
You still need enough clearance between the tamped coffee and the shower screen above it. If the dry puck is being pressed into the screen when you lock in the portafilter, before you’ve even brewed anything, check your dose and basket choice.
Once you’ve found a sensible dose for your setup, I’d keep it steady while dialling in. My espresso guide to dose, yield and time goes into that part in more detail.
Good distribution goes all the way through the basket
What is WDT, and why do we use it?
WDT stands for Weiss Distribution Technique. It involves using fine needles to stir through the ground coffee, break up clumps and distribute it more evenly before tamping.
A simple handheld WDT tool lets you do this manually. Work gently through the depth of the grounds, covering the whole basket, then finish with a reasonably even surface.
In the café, we use an MHW-3BOMBER Cyclone, which rotates needles through the coffee when you press it.
It’s worth distinguishing this from the solid spinning levellers you might have seen sitting on top of a basket. Our tool uses needles to work through the grounds; it isn’t just smoothing the surface.
For us, it makes this part of the routine quick enough to use during service.
I’ve found that pushing it too vigorously tends to throw coffee towards the sides of the basket. A slower, gentler movement gives us a better result. More enthusiasm isn’t necessarily helping here.
Should you tap the portafilter?
After distributing, I like to give the side of the portafilter a couple of gentle taps with my hand to settle the grounds into a level bed.
Then I tamp.
What I avoid is knocking the portafilter after tamping. You sometimes see a routine of tamp, knock the side to dislodge loose grounds, then tamp again.
To me, that’s an extra step with very little benefit. You’ve already formed the puck, and knocking it can disturb it or separate it from the basket wall.
I’d much rather get the distribution right, tamp once and leave it alone.
How hard should you tamp espresso?
Firmly enough to compress the loose coffee into a stable puck. You don’t need to put your entire body weight into it.
As you press, you’ll feel the grounds settle and the resistance increase. Once the bed is firmly compressed, pushing harder and harder achieves very little.
I’m much more interested in a level, repeatable tamp than an impressive amount of force.
This brings me back to tamping in mid-air. Resting the portafilter securely on a tamping mat or suitable support gives you something stable to work against. I find it much easier to press straight down and keep everything level that way.
There’s enough going on when you’re making espresso without balancing the whole thing in your hands.
Why we use a PUSH tamper
We’ve had really good results with a PUSH tamper in the café.
It has a flange that rests on the basket rim and an adjustable tamping depth. Once it’s set correctly, that helps us tamp level and repeat the same depth between baristas.
The setup matters, though. It needs to reach far enough to compress the coffee properly, so check the adjustment when changing your dose, basket or coffee.
You can absolutely get good results with a conventional tamper. I just like taking some of the variation out of a busy café routine.
And logically, you'll get a better more consistent pressure if you tamp against a flat even surface, straight down! Don't hover the portafilter in mid-air?!
Why we grind into dosing cups
We grind into small cups before transferring the coffee to the basket.
For us, the biggest advantage is workflow. Our EK43 takes a little while to grind a dose, and using cups means we can grind the next coffee while another shot is pulling.
We actually use 125ml wine measures. I’ve adjusted their weights so they all weigh the same, which means we can use the same tare on the scales to check each dose.
It’s a slightly homemade solution, but it works really well for us.
Our house coffee is dosed through a Titus dosing system on the EK43, while the other coffees are pre-weighed. Either way, we check what has actually landed in the cup before transferring it to the basket.
At home, you might prefer grinding straight into the portafilter. The important thing is knowing how much coffee is going into your shot and distributing it properly once it’s there.
Why I prefer bottomless portafilters
We use bottomless portafilters at Bond Street, and I find them incredibly useful.
Being able to see the underside of the basket lets us watch how each shot develops. Obvious spraying or uneven flow gives us a reason to look more closely at what’s happening.
It isn’t a perfect diagnosis. A pretty-looking shot can still taste disappointing, and not every extraction problem is visible. But it gives us information we’d otherwise miss.
I’m so used to seeing the coffee come out now that using a spouted portafilter feels quite strange.
Spouts make sense if you want to split an espresso between two cups. For our routine, though, I prefer the visibility of a bottomless portafilter, and I find it easier to keep clean. There are fewer little spaces for coffee oils to collect.