When the burrs in an EK43 are not concentric with the motor shaft, the gap between the stationary and rotating burr varies around the circumference. That variation produces an uneven grind: some particles are ground finer than intended, others coarser. The result is less consistent extraction in the cup. This alignment tool corrects the problem by centering each burr radially on its mounting point, so the gap stays uniform at every position. The tool uses a three-point contact design that holds the burr in position while a centering rod references off the drive shaft (for the stationary burr) or the pre-breaker (for the rotating burr). Once placed, you tighten the three burr screws, remove the tool, and reassemble. The whole procedure takes a few minutes per burr. When and why to use it Mahlkönig recommends realigning the burrs every time you replace or remove them. Even if you are just cleaning the grinding chamber, removing and reinstalling the burrs without re-centering can introduce slight radial misalignment. Many EK43 owners also report that factory alignment can benefit from a check, so running the tool on a new grinder is worthwhile. Note that this tool addresses radial alignment only. It does not correct parallel (axial) misalignment or warped burrs, which require different techniques such as shimming with a dial indicator. Specifications Part number 105866 Compatibility EK43, EK43 S, EKK43 (all pre-breaker variants) Alignment type Radial (concentricity) Tool material Aluminum Centering rod material Steel Additional tools required Slotted screwdriver, brush or vacuum for cleaning What’s in the box Aluminum burr alignment tool Steel centering rod Food-safe grease Illustrated instruction manual
