Puck prep

Puck prep covers everything done to the loose coffee grounds after grinding but before tamping, including distributing the grounds evenly across the basket and breaking up any clumps, often with a WDT tool. The goal is a level, evenly dense bed of coffee before any pressure is applied to it.

Good puck prep matters because tamping alone cannot fix an unevenly distributed bed; pressing down on grounds that are piled higher on one side simply locks that unevenness in place instead of correcting it. Since channeling almost always starts from weak spots created before tamping, most of the work that prevents it happens during puck prep, not during the pour itself.

A typical routine is to distribute the grounds with a tool or by hand, stir with a WDT tool to clear clumps, level the surface, and then tamp firmly and evenly. A common mistake is rushing straight to tamping after grinding, skipping distribution entirely, which is one of the most common causes of channeling in home espresso setups.