Rotary cutting tool with pairs of helical cutting edges having different helix angles

A rotary cutting tool, comprising:

• a substantially cylindrical main body having a shank portion at one end and a point at an opposite end;
• a first pair and a second pair of flat cutting edges positioned on opposite sides of the main body at the point, wherein the first and second pairs of flat cutting edges are interleaved;
• a first pair of flutes formed on opposite sides of the main body, wherein each of the first pair of flutes extends continuously from the from a different one of the first pair of flat cutting edges to the shank portion and defines a helical cutting edge having a helix angle of about 37 degrees with respect to an axis of the main body;
• and
• a second pair of flutes formed on opposite sides of the main body, wherein each of the second pair of flutes extends continuously from the from a different one of the second pair of flat cutting edges to the shank portion and defines a helical cutting edge having a helix angle of approximately 33 degrees with respect to the axis of the main body.