A component of an ion optical device is manufactured. The component comprises aligned first and second electrode sets. A first material is machined to provide a part-machined first electrode set that comprises the first electrode set attached to a frame part of the first material. A second material is machined to provide a part-machined second electrode set that comprises the second electrode set attached to a frame part of the second material. The component of the ion optical device is assembled by aligning the part-machined first and second electrode sets. Subsequent to aligning the part-machined first and second electrode sets, the part-machined first electrode set is further machined to separate the first electrode set from the frame part of the first material and the part-machined second electrode set is further machined to separate the second electrode set from the frame part of the second material.