Want to make a perfect espresso or cup of coffee?
If the answer is yes then you better make sure your grinder is up to the task because even a $20,000 super machine will make a terrible shot if paired with poorly ground coffee.
(To skip to the tutorial section scroll down)
To emphasize the importance of a properly calibrated and tuned grinder, below are some tech support questions we answer daily.
My coffee comes out too fast and is watery, what's wrong with my machine?
My espresso is super slow and taste bitter, what's wrong with my machine?
My machine isn't making any crema, what's wrong with it?
My pressure gauge never goes above 4 bar and the machine is new, is the pump defective?
I'm not getting any coffee out of the machine at all, is it broken?
Beginning to see a theme? More often than not, the answer is the machine is completely fine and the grinder was either set incorrectly or the person was using the wrong kind of coffee.*
*Yes, there is a right and a wrong kind of coffee for an espresso machine. This topic is covered in depth in a separate article.
Now onto the grinders, before we discuss how to adjust your grinder, let's identify if your grinder is appropriate and ready for espresso duty.
Grinders are split into two main categories: Burr Grinders (e.g. Mazzer Mini Electronic) and blade grinders (e.g. this thing). If you have a burr grinder, awesome! If you have a blade grinder... it's time to get a burr grinder as a blade grinder will never make for good espresso.
There are thousands of burr grinders to choose from and you will see words like flat burr, conical burr, stepless, on demand, doser, electronic, timer, and the list goes on forever. In the end they can all make good espresso if they are high quality and if you want to talk to a Pasquini sales rep on choosing the best grinder, click here to contact us or email firstname.lastname@example.org.
Once you have identified you have a proper burr grinder, evaluate its age. Most grind stones on a burr grinder last 5-10 years with average residential usage. If your grinder is way older than that, then we suggest to replace the burrs as trying to adjust a worn out grinder is a great way to waste time and coffee.
Grinder Calibration Tutorial
Now with all of the pre-requisites out of the way, we can begin to calibrate our grinder. Follow the steps below to calibrate any new or existing grinder:
Note: If you have an electronic dosage grinder, use the manual button to calibrate and do not set the dosage until you have completed your calibration.
- Check for numbers on the adjustment mechanism, if the grinder does not have numbers perfect, if it does have number promptly ignore them. The numbers do not mean anything. you can have two of the exact same grinders with completely different number settings that produce the same result.
- Grind coffee from the grinder and feel its consistency. If it feels like flour it is far too fine and if it feels like coarse beach sand it is not fine enough.
- Depending on your current setting, make a small adjustment (this varies depending on the adjustment mechanism but rule of thumb would be for collar adjusters no more that 1-2 inches of movement and for spin dial adjusters no more than 1 full turn). Note: If you make too large of an adjustment at once you risk jamming your grinder so make small adjustments and grind in-between each movement.
- Now that you have adjusted the grinder, run it for 3-5 seconds to purge the old grind setting from the chamber and ensure all coffee coming out is only that from the new setting.
- Repeat steps 2-4 until the grind feels somewhere between coarse beach sand and flour.
- Now with your new grind setting make a shot on your espresso machine. We recommend to use a scale when you first set up your grinder to remove as many variables as possible so you are only testing the grind setting and not changing the shot due to weight fluctuations.
- Evaluate the shot. If your machine has a brew pressure gauge it should be at 9 bar (8-10 bar is also okay depending on the coffee's roast profile). If your machine does not have a brew pressure gauge, look at the stream of espresso. If the stream is solid, smooth, and about 2-3mm thin then you are okay. If the stream drips and is broken your grind is too fine and if the stream is 1/4 in thick and fast/bubbly, your coffee is too coarse.
- If your shot is good you are done! If the shot is outside of the desired range then repeat steps 2-7 until the coffee is withing the correct margin for espresso.
- For those with an electronic dosage, you can now program the shot timers with your new grind setting.
- One last thing... If you switch your coffee to a different one or if the whether goes from dry to humid, or if your burrs simply wear down, you will need to readjust your grinder. Grinder settings are not permanent nor are they universal so make sure to be comfortable with the above steps and do not be afraid to calibrate the grinder often to ensure you are getting the best possible shot.
If you are having trouble dialing in your grinder, please feel free to contact us so our professional baristas can assist you. We even offer free grinder calibration for anyone that purchases or has purchased a machine or grinder from us. Schedule an appointment here.