Abstract: A milling tool is disclosed. The milling tool may include an elongated body having a longitudinal axis and a plurality of cutting inserts. The cutting inserts may each have a cutting edge and a cutting radius and be coupled to the body and spaced along the longitudinal axis. One or more of the plurality of cutting inserts may be adjustable (e.g., mechanically adjustable) between first and second cutting radii. A difference between the first and second cutting radii may be at least 10 ?m. The milling tool may include cutting inserts having a plurality of different cutting radii. The milling tool may be configured to have a length that spans an entire height of an engine bore. The cutting inserts having different radii may compensate for dimensional errors in an engine bore diameter that occur when milling a deep pocket.

Abstract: A method of milling an engine bore is disclosed. The method may include inserting a milling tool having a plurality of cutting edges along a longitudinal axis into an engine bore, rotating the milling tool about the longitudinal axis and moving the milling tool around a perimeter of the engine bore to remove material from the engine bore, and rough honing the bore. The milling may generate a tapered bore (e.g., frustoconical). The rough honing process may increase a minimum diameter of the tapered bore by at least 60 ?m. A total time of the milling and honing process may be less than 60 seconds. In one embodiment, the honing step may include using a grit size of at least 200 ?m and/or using a honing force of at least 200 kgf. The method may reduce the cycle time and tooling requirements of forming engine bores.

Abstract: Milling tools configured to increase surface roughness are disclosed. The tool may include an elongated body having a longitudinal axis and a plurality of cutting inserts coupled to the body and spaced along the longitudinal axis, each cutting insert having a cutting edge. In one embodiment, the cutting edges may have an orientation that is oblique to the longitudinal axis of the elongated body. Each cutting edge may have a first end having a greater cutting radius than a second end. The cutting edges may be offset from the longitudinal axis of the elongated body by an offset angle. In another embodiment, the cutting edges may have a textured or rough surface profile. For example, the cutting edges may have a mean roughness (Rz) of at least 7.5 ?m. The milling tools may increase the surface roughness of a milled engine bore to facilitate a subsequent rough honing process.

Abstract: A milling tool is disclosed. The milling tool may include an elongated body having a longitudinal axis and a plurality of cutting inserts. The cutting inserts may each have a cutting edge and a cutting radius and be coupled to the body and spaced along the longitudinal axis. One or more of the plurality of cutting inserts may be adjustable (e.g., mechanically adjustable) between first and second cutting radii. A difference between the first and second cutting radii may be at least 10 ?m. The milling tool may include cutting inserts having a plurality of different cutting radii. The milling tool may be configured to have a length that spans an entire height of an engine bore. The cutting inserts having different radii may compensate for dimensional errors in an engine bore diameter that occur when milling a deep pocket.