Selecting a diamond micro drill starts with the hole you must produce. Define the material, diameter limits, depth, position, edge condition and production requirement. Then match the tool construction and geometry to the capability of your machine and inspection process.

Composite machining rarely fails because the abrasive is simply "not hard enough." The more common problem is a mismatch between the composite structure, tool construction, machine conditions, and the quality requirement. A CFRP component may suffer delamination while a GFRP part shows fiber pullout. Aramid can produce fuzzing, honeycomb can collapse at the cell wall, and ceramic matrix composites can develop matrix cracking or fiber damage. The same diamond tool specification for composites should not be expected to solve all of these problems.

Grit, bond, kerf, and material selection — treated as a system problem, not a catalog lookup. Precision sectioning is often treated as a blade selection problem. In practice, the blade is only one part of the cutting system. A diamond wafering blade with the correct diameter and arbor can still produce excessive chipping, material deformation, poor surface finish, blade deflection, overheating, or unacceptable material loss. The result depends on the relationship between material, diamond mesh size, concentration, bond, blade thickness, kerf, machine capability, coolant, feed, speed, and workholding.

Choosing a diamond core drill bit starts with the material, the finished hole, and the equipment that will produce it. Diameter matters, but two drills with the same nominal diameter can behave very differently. Their cutting-wall thickness, diamond grit, bond, usable depth, and mounting arrangement all influence the result.