Analysis
The data indicates a very fast turbo shot with evidence of channeling. The average flow rate of 6.0 ml/s is high, and the erratic flow pattern (ranging from 4.2 to 7.5 ml/s) while pressure remains relatively stable is a strong indicator of channeling. The total shot time of 14.3 seconds is also very short for an 18g dose to 36g yield, suggesting low resistance and fast extraction. The preinfusion phase shows a rapid flow rate of 6.8 ml/s, which could be contributing to the channeling.
Primary Issue
Channeling - The erratic flow pattern at a relatively stable pressure points to water finding preferential paths through the puck.
Recommendation
Adjust: Puck Preparation How: Improve puck preparation to reduce channeling. Specifically focus on distribution and tamping. Try the following:
WDT (Weiss Distribution Technique): Use a needle or similar tool to break up clumps and evenly distribute the coffee grounds in the basket before tamping.
Consistent Tamping: Ensure a level and consistent tamp every time. Aim for consistent pressure (around 30 lbs) without excessive force. Why: Addressing puck prep will help create a more uniform resistance across the puck, reducing the likelihood of water finding easier paths and causing channeling. Improved distribution eliminates density variations. Consistent tamping avoids localized compaction.
What to Look For Next Shot
Next shot, observe for a more stable and predictable flow pattern. Ideally, the flow should still be high, but smoother and more consistent, without the large fluctuations. Also, look for the flow to start a little later and build more consistently, rather than the initial rush. If the channeling persists, it may indicate that the coffee is too coarse and a grind adjustment will then be needed, however, improved puck prep should be the first focus.
Important Context
It is important to address puck prep issues BEFORE considering a grind change. A more consistent puck will provide a better baseline for evaluating whether a grind adjustment is actually needed. If, after improving puck prep, the channeling continues and the flow remains excessively high, then consider grinding finer.
Advice by Google Gemini
Analysis
The data indicates a very fast turbo shot with evidence of channeling. The average flow rate of 6.0 ml/s is high, and the erratic flow pattern (ranging from 4.2 to 7.5 ml/s) while pressure remains relatively stable is a strong indicator of channeling. The total shot time of 14.3 seconds is also very short for an 18g dose to 36g yield, suggesting low resistance and fast extraction. The preinfusion phase shows a rapid flow rate of 6.8 ml/s, which could be contributing to the channeling.
Primary Issue
Channeling - The erratic flow pattern at a relatively stable pressure points to water finding preferential paths through the puck.
Recommendation
Adjust: Puck Preparation
How: Improve puck preparation to reduce channeling. Specifically focus on distribution and tamping. Try the following:
- WDT (Weiss Distribution Technique): Use a needle or similar tool to break up clumps and evenly distribute the coffee grounds in the basket before tamping.
- Consistent Tamping: Ensure a level and consistent tamp every time. Aim for consistent pressure (around 30 lbs) without excessive force.
Why: Addressing puck prep will help create a more uniform resistance across the puck, reducing the likelihood of water finding easier paths and causing channeling. Improved distribution eliminates density variations. Consistent tamping avoids localized compaction.
What to Look For Next Shot
Next shot, observe for a more stable and predictable flow pattern. Ideally, the flow should still be high, but smoother and more consistent, without the large fluctuations. Also, look for the flow to start a little later and build more consistently, rather than the initial rush. If the channeling persists, it may indicate that the coffee is too coarse and a grind adjustment will then be needed, however, improved puck prep should be the first focus.
Important Context
It is important to address puck prep issues BEFORE considering a grind change. A more consistent puck will provide a better baseline for evaluating whether a grind adjustment is actually needed. If, after improving puck prep, the channeling continues and the flow remains excessively high, then consider grinding finer.
Advice by Google Gemini