How to make great coffee with the ROK espresso maker

I love my ROK espresso maker

In my collection of coffee gadgets, the ROK espresso maker is easily my favourite coffee maker. I’m 8 years into my love affair with the ROK and every morning I’m still amazed at the quality of the coffee it produces. No matter where I go, if I have hot water, I have great coffee.

I want to share a few things I’ve learned over the years and kickstart your ROK adventure. The ROK isn’t a one-click automatic espresso machine and there’s a few things you’ll need to do to make sure you get the most delicious espresso possible. Good luck and have fun!

How to choose coffee for the ROK espresso maker

For the ROK to really shine, you must use freshly-roasted coffee. That is coffee that has a roast date of no more than 7-10 days prior to purchase. Using cheap, old, stale or pre-ground coffee is going to put you at a disadvantage. Bad beans will produce flat, bitter espresso with little to no crema.

Preheating the ROK (optional)

This is an optional step, but you can preheat the ROK by adding hot water to the top chamber and letting it sit while you prepare your beans, and get organised. Insert the portafilter (no coffee) while you’re preheating so you can neatly press out and discard the water.

I always preheat my ROK. I find it reduces heat loss from the water while I’m making coffee. This ensures I’m making the best espresso I can.

How much coffee should I use?

The ROK performs best with a dose of between 15 and 18 grams of fresh ground coffee. I treat my coffee like a recipe. Get the ingredients and measurements right and I can enjoy consistently good coffee, day after day.

I use a kitchen scale to measure my beans for each coffee. If you don’t have access to a scale, the basket in the portafilter holds around 18 grams of whole coffee beans.

How fine should I grind?

With the correct espresso grind setting, the levers will require only a moderate amount of force, and your espresso should trickle out in a viscous stream, producing crema-rich espresso.

If you don’t grind fine enough, the ROK’s levers will be very easy to push down and the espresso will gush out, giving you a watery, bland cup of coffee.

If you grind too fine, the levers will be very hard to push down and the espresso may only drip, or not come through at all. Don’t force the levers if you suspect you’ve ground too fine. Trying too hard to push the levers down can damage the ROK or cause hot water to spray out of the chamber, potentially causing injury.

I recommend starting a little coarser and adjust your grinder a little finer for each shot, until you find you sweet spot.

Grind fresh. For the best espresso, grind just enough beans for each cup. Grind right before you make your coffee as ground coffee stales quickly.

How heavily should I tamp?

Tamp firmly, but not too hard. Tamping too hard creates dead spots where the water can’t pass through the coffee bed. Tamp too softly and the water will pass too quickly through the coffee, leading to channeling and under-extraction (boring).

I practiced by tamping on a bathroom scale, applying 12-13 kg of force. I don’t make enough coffees each day to perfect my tamping technique, but I aim just to be in the ballpark.

How much water should I use?

Filled to about 1-2 cm from the top, you can fit about 100 ml of water in the top chamber. Ideally your espresso will be around 30-40 ml. So you’re not aiming to get all the water from the top chamber into your cup (it will taste crappy if you do).

How to press the levers

If you have the grind and dose right, you should only need to press the levers once. Press firmly, but don’t overdo it. I slow the press once the first drops of espresso hit my cup. Then, when the espresso is at the desired volume (30-40 ml) release the levers. You’ll hear a hiss as the remaining pressure is released.

Place a new cup under the ROK and press out the remaining water. This will make clean-up easier, when you remove the portafilter.

Clean and dry your ROK!

Cleaning is easy. When you’re finished making coffee, flush the ROK with clean water to remove coffee grounds and oils.

Dry the ROK thoroughly before putting it away! Keeping the ROK dry between uses will keep it looking shiny. Leaving the ROK wet will cause the aluminium to oxidise and it will lose its lustre. Remove the flexible white filter screen from underneath so the inside can dry out.

Above all, have fun!

I’ve known plenty of folks who produced great coffee from the ROK, right off the bat. It took me a little while to get to where I really felt I had figured it out. The ROK isn’t a push-button solution. Get hands-on, be patient and have fun experimenting. The reward is delicious!