Radius milling is a form of contour milling. Corner round tools are available in high speed steel, carbide, or insert type tools.
Figure 7.13: Radius Milling
Rules for Radius Milling
The horizontal and vertical cutting edges of a radius mill are sloped slightly to blend the radius into the walls.
Take two finish passes to improve surface finish.
Another way to form a corner radius is to use a ball mill and 3D contour tool path. This method saves purchasing a radius mill and is suitably efficient for prototype and small production manufacturing.