Recap

• Burr size, sharpness, and alignment have measurable effects on the grind size distribution. That is why these factors are so important in brewing.
• A grinder in use creates heat, which increases the temperature of the ground coffee. In some cases this temperature can rise to as high as 100° C (212° F).
• These temperature changes affect shot time and extraction.
• The effect of temperature changes seems to relate not to metal parts expanding in the grinder,