Chemex Brewing Guide The Chemex is a historical piece of brewing equipment. It was invented in 1941 by Peter Schlumbohm and was so revered that it was placed into the Museum of Modern Art in New York City. It uses proprietary filters, made of chemically bonded paper (of thicker-gauge paper than the usual paper filters for a drip-method coffeemaker), which removes most of the coffee oils associated with an immersion brew. It therefore brews and tastes differently than the coffee brewed with other methods. Step 1 Weigh out your coffee; it’s important! We like to use a 1:16 or 1:17 ratio of coffee to water. For this example, we will be using 50g of coffee and 800g of water. Step 2 Grind it coarsely with a quality burr grinder. (Aim for the consistency of coarse sea salt) Step 3 The square Chemex filters are folded so that it is four sheets thick. Open the filter without unfolding it, and place it into the opening of the Chemex with the three sheets against the spout side. Step 4 Paper filters are notorious for absorbing odors and flavors in storage. They also have a water-soluble element that tastes like paper. Rinse about a half liter of just-boiled water through the filter. This will rinse the papery taste out and also serve to preheat the vessel. Step 5 Pour the rinse water out through the Chemex spout before you start your brew. We’ve all made this mistake; save yourself the redo. You shouldn’t have to remove the filter for this, but you’ll want to do it slowly so as to not deform the filter. Step 6 Place the Chemex on the scale, add the coffee, and tare out the scale. (You might want to tare out the scale before the coffee as well, just so that you can verify that your dose hasn’t changed) Step 7 Using a gooseneck kettle, quickly add just enough brew temperature water to cover the coffee to allow it to degas. (this should be ~100g) Step 8 Use a spoon or stirrer of some sort to agitate twice away from your body and then twice left to right. (agitation will quicken the extraction, so it’s important that your actions are very precise and repeatable) Step 9 Allow the coffee to degas and bloom for ~35 seconds after your pour. The timer should reach no later than 00:45 (This is somewhat dependent on how fresh your coffee is, but 35 seconds after your pour is a good baseline) Step 10 Start your pour slowly but consistently, totaling 400g on the scale by 1:30, then stop. This is just under 7 grams per second. If you’re having trouble pacing, a good rule of thumb here is to pour so that the stream is falling almost straight down. Step 11 Wait 15 seconds, then continue with your pour, adding 200g (total of 600g) by 2:30. Step 12 Repeat step 10, adding 200g (total 800) by 3:30. Brewing should end not later than 5:00. If the brew takes too long, your grind is probably too fine. If it drains too quickly, your grind is probably too coarse.