The paper deals with a progressive method of modification of cutting tools by drag finishing process. The subject of the research is the dependence of the drag finishing time on the size of the cutting edge radius. The milling tool - solid cemented carbide mill was made on a tool grinder REINECKER WZS 60. The cutting tool was drag finished on the OTEC DF-3 TOOLS drag finishing machine. The measurements of cutting edge radius was performed on two devices: 3D optical microscope ALICONA Infinite focus G5 and contour and surface measuring machine ZEISS SURFCOM 5000. The results of the measurements are evaluated at the end of the paper.

The paper describes the design and implementation of a cutting fluid monitoring system, as well as the design and development of an algorithm to increase the life of the cutting fluid in the machine tool reservoir. Cutting fluids are the most common type of coolant in machining. During its use, it becomes contaminated and gradually degrades until it needs to be replaced with fresh fluid. To increase its effective service life, its parameters should be monitored at regular intervals, and corrective measures such as topping up the fluid quantity and adding inhibitors and additives should be taken if necessary. For this purpose, a conceptual design of a monitoring device was developed, and a prototype device was subsequently manufactured. The device is designed as a floating probe in the storage tank. Therefore, its shape had to be designed to accommodate multiple sensors, batteries, and electronic components while remaining floating and watertight. The designed prototype was made by additive manufacturing and placed in a cutting fluid while being measured at regular intervals. In the event of non-compliant parameters, the algorithm generated corrective actions, and the machine operator could take the required steps to significantly increase the lifetime of the cutting fluid.

The turning of small-diameter deep holes is usually critical when the process of machining is unstable and the use of a special boring bar is often necessary. This paper is focused on the influence of cutting speed with a combination of cutting conditions such as feed and tool overhang on chatter marks, surface roughness and roundness of machined holes. In the experiment, two types of tool material for indexable boring bars were used, namely cemented carbide and steel. These are a group of boring bars used for the internal turning of holes of small diameters with indexable cutting inserts. Monolithic carbide boring bars are already used for internal turning of holes of even smaller diameters. Uncoated turning inserts made of cermet were used. The cutting tests were performed on the DMG CTX alpha 500 turning center. In the case of the steel boring bar, decreasing the cutting speed really led to an increase in the quality of the surface roughness and reduced the formation of chatter marks and large chatter marks. The cemented carbide boring bar also followed a similar trend, but it should be noted that the overall effect was not so great. This means that increasing the cutting speed makes the cutting process less stable and, vice versa, lower values of cutting speed reduce the formation of chatter marks and the related deterioration of the surface quality. The occurrence of chatter is directly related to the increase in the surface roughness parameters Ra and Rz of the machined surface. It can be stated that the dependence of roundness deviations on cutting speed values has a similar character to the results of the measured surface roughness values. Therefore, if the cutting speed is increased, it will make the cutting process less stable; this is also indirectly reflected in larger roundness deviations. However, it is necessary to state that this phenomenon can be observed in turning holes with small diameters using the steel boring bar, where the unstable cutting conditions materialized in the form of chatter marks.

The aim of the experiment described in the paper was to determine the possibility of using an optical 3D scanner to measure the macro-geometry of cutting tools. To verify this possibility, a precise component was measured, and the accuracy of optical 3D scanner was compared to a tactile coordinate measurement machine. A precise cemented carbide rod was used as a reference part and the measurement data were compared with the measurement result from the ZEISS Prismo coordinate measurement machine. The data obtained from the measurements were evaluated and compared. The experiment was carried out so that the use of an optical 3D scanner to measure cutting tools could be verified based on the desired requirements. Both dimensions and geometrical tolerancing – circularity were measured. The experiment has shown that an optical 3D scanner can achieve sufficient accuracy for the purpose of measuring macro-geometry of cutting tools.