Carbon-fibre-reinforced plastic is prominent with superb specific mechanical properties that contribute to its application in high technology industries, such as aircraft and automobiles' mechanical structures. These materials are considered hard to cut. The delamination issues frequently arise due to their anisotropy and inhomogeneity. In aircraft manufacturing, thousands of holes are required to assemble the structural parts. Hole perpendicularity issues undoubtedly might happen during manual drilling. The main purpose of this work is to study the effects of various minor slant drilling angles on thrust force generation and delamination by using a special drill reamer. From the investigation, the drilling penetration angle significantly impacted the delamination. The delamination factor for the entry and exit sides of holes relatively decreased from 1.042 and 1.087 to 1.027 and 1.049, respectively, as the thrust force declined from 114.8 N to 106.5 N from 5° to 0° drilling angle.