Method for machining and forming a transcurrent opening in a fiber-reinforced composite material

A method of machining a transverse opening in a fiber-reinforced composite material, said method comprising the steps of:

• forming a hole in a composite material, said composite material being of laminated construction with each lamina having a plurality of fibers oriented in a respective longitudinal direction, said forming step resulting in delamination and splintering of said formed hole about a radial periphery thereof;
• positioning a rotatable cutting tool in the formed hole, said cutting tool having a wear-resistant outer working surface and a diameter which is smaller than a diameter of the formed hole, said cutting tool defining an axis of rotation;
• positioning the composite material whereby said axis of rotation is disposed substantially perpendicular to each said respective longitudinal direction;
• and
• machining the transverse opening in the composite material by rotating the cutting tool about the axis of rotation and moving the cutting tool relative to an edge of the formed hole, said moving of the cutting tool dependent on a radial extent of any physical defects in the composite material caused from making the formed hole, whereby substantially all of said physical defects caused from making the formed hole are removed from the composite material, the transverse opening having at least one of a size and geometry which is substantially different from a corresponding at least one of a size and geometry of the formed hole;
• wherein said machining step further comprises moving said cutting tool in a direction which is substantially parallel to each said lamina at said formed hole.