“Tiny” usually comes to mind when the term “micro” is used. So it is easy to assume that micromachining equates to operations performed on very small parts found in the medical and electronics manufacturing industries. However, this isn’t always the case. Many large workpieces require very small features that can only be accomplished by micromachining techniques.

Jack Burley, VP of sales and engineering at Big Kaiser, says Sphinx (a product line distributed by Big Kaiser) defines micro-drilling with a starting diameter of 0.05 mm (0.002 inch) and ranging to 2.5 mm (0.10 inch). This very small drilling requires a machine tool that has very high sensitivity and fine resolution in the feed axis. Machines must also have very precise spindles capable of high speed rotation with low dynamic runout.

Not only does the type of machine matter, but the type of material makes a difference as well. Matching the material to the cutting tool is similar to conventional drilling operations except that in micro-drilling, even more attention must be given to the sharpness and centering of the cutting edge. By varying the geometry of the drill and the material from which the tool is made, micro-tool makers can influence the performance of tools in different materials.

Other important factors for micro-drilling include tolerances, required hole depth, the drill’s entry point, the number of holes and operator skill level. To learn more about these factors and other information about micro-drilling, read “Micro-Drilling: Some Questions to Think About.”

What would you like to see here next month? Are there any technical processes you would like to know more about? If so, please e-mail me: lbeckman@productionmachining.com.