The fineness/coarseness of ground coffee plays an important role in the brewing process of coffee, and it is important to match the grind with the method of brewing. Brewing methods that expose the grind to water for longer periods during the extraction process, such as drip coffee making and percolation, are best suited to a coarser grind. Otherwise, coffee over-extraction may result in a rough, bitter taste. In faster methods of coffee brewing, such as espresso (pressurized) extraction, a finer grind is preferred. Otherwise, under-extraction may result in a sour, watery result. In the world of grinding coffee, there are two basic types of grinders: the burr grinder and the blade grinder. At 125West, we carry only burr types, since they are suitable for all coffee brewing methods. Two revolving burrs, which have been machined from hardened steel or ceramic, crush the coffee beans into consistently-sized smaller particles (i.e. milling). By adjusting the distance between the burrs, the user can mill from powdery fine to coarse. Another advantage of a burr grinder is its slower milling speed, which minimizes any heating effect to the coffee during the milling process and thus conserving flavor and aroma. Most burr grinders today are powered by an electric motor, although we do sell hand-cranked mill made by Peugeot. If you are looking for a true commercial-quality grinder for the home, the consider the Gaggia MDF mill.