A general algorithm for drilling holes lying in a matrix

Canned cycles provide a programming method of the motion of an axis of a CNC machine to accomplish repetitive machining operations, using the standard G-code. However, the standard canned cycles are limited in number and capability. For this reason, modern CNC units have the capability of creating similar cycles, called user-defined cycles, for different machining operations. The creation of user-defined cycles is not a simple task and needs much more technical experience and a lot of trails. This paper describes an investigation to develop a general programming algorithm in G-code for drilling holes lying in a matrix in an easy way. This algorithm may be used for creating user-defined cycle and/or subroutines for drilling holes lying in a normal matrix, a staggered matrix, a single row, and/or column. This programming algorithm is useful for machining boilerplates, drum and trammel screens, and separators. For testing the capability of this developed algorithm, several work-pieces are machined with satisfactory results. An example of such machined pieces is presented. The developed algorithm saves about 99% of the time required to prepare the part program in addition to reducing programming error.