Holes Used in PCB: Mechanical hole

There are many types of holes used in PCB circuit boards, such as blind holes, buried holes, and through holes, as well as BB holes(Blind-Buried Holes), micro holes, mechanical holes, countersunk holes, staggered holes, stacked holes, first-order holes, second-order holes, third-order holes, arbitrary order holes, guard holes, slot holes, back drilled holes, PTH holes, and NPTH holes.

Mechanical hole

Mechanical holes, also known as large holes, are holes processed using mechanical processing methods such as drilling, grinding, boring, gongs, and hinges. The smaller the diameter of the hole, the thicker the board, making it more difficult to process. The current smallest mechanical hole diameter is 0.15mm, which is also the most commonly used type of hole on PCB circuit boards.