Knife Cutter,Best Box Cutter,Retractable Utility Knife,Paper Cutting Knife YUCHENG RUNJIA MEASURING TOOLS CO.,LTD , https://www.duobangtools.com For the dimensional tolerance of the hole; the distance tolerance between the hole and the hole; the distance between the hole and the base, such as the tolerance of the workpiece, if the hole depth exceeds 500mm, it will bring considerable difficulty to the processing. For example, to machine a piece of φ150_0~(+0.02)mm, the hole depth is 500mm, the two holes are 300±0.02mm, the cylindricity tolerance is 0.015mm, and the workpiece with the bottom reference parallelism of 0.03mm is guaranteed.