Easy Cold Brew Coffee Maker

thingiverse

UPDATE Sep-6, 2021 I added a new filter design. It offers slightly larger holes and, most importantly, a way to use a regular rubber band as a sealing gasket. Once the filter is pushed in, water will no more flow through the little gaps between the vessel and the inlay, thus providing for a much more consistent coffee result :) DESIGN This is a simple to use Cold Brew Maker. It requires a permanent filter so sit in the inlet at the bottom. Im using a size 2 filter, which in my case has a diameter of 9.2 cm (~3.6 in). You will need to adjust the inlet according to the diameter of your filter and the measurements of its upper lip, as those do vary a bit. The concept is very straight forward. Place the vessel on a pot or glass of your choice. Add ground coffee into the permanent filter and then placed in the inlet. On top of it place the concave disc with holes in the center to separate the ice cubes from the coffee and distribute the water from the thawing cubes somewhat evenly. Fill the vessel up with ice cubes and close it with the lid. The construction should yield about 500-700 ml (roughly17 to 24 fl. oz) within 10 to 16 hours, depending on your room temperature and the size of the ice cubes. For extra careful but longer processing you can put everything in the fridge. Empty the filter when done and wash everything by hand before you go again. The taste of the coffee can be varied via the fineness of the coffee grind, the amount of coffee used (70% of the filter's height is a good starting point) and of course the type of coffee. Make sure your filament is declared as food safe by the food agency of your region. I used PLA which in most cases fulfills that requirements. Optionally you can also apply a food safe coating. Always check the manufacturer's declaration. Use ABS or PEI if you want to be able to put it into the dishwasher without causing deformation.