The tamp is uneven or sloped
The puck surface slopes visibly, or the shot consistently runs faster on one side than the other.
Applies to: Espresso machine, Espresso
Likely causes and adjustments
Try one adjustment at a time so you know what actually changed the result. Start with the first cause below — if it doesn't help, reveal the next.
Cause 1 of 4 · Commonly the cause
Portafilter held in the air or resting at an angle while tamping
Rest it on a flat surface or a tamping mat so the basket is horizontal.
Related issues
Learn the technique
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