The evaluation of the measuring capability of a measuring device is very important in the field of quality assurance. It is a part of a measurement system analysis. One of the measuring devices is the optical 3D scanner which is device for object digitization, in substance. This paper deals with the possibility of measuring a small objects, namely hard metal rod which is a semi product for cutting tool, e.g. end mill. The issue was the evaluation of the measuring capability of the GOM ATOS Triple Scan II optical 3D scanner when measuring the dimensions, i.e. tool diameter, with using of different measuring volumes. Measuring of a small objects is often difficult due to ensuring the measuring repeatability and low bias. Capability evaluation was performed using statistical methods, namely indices which define the measuring device capability. The work contributed to the practical knowledge about abilities of ATOS optical 3D scanner in reverse engineering and measuring processes, and to the determination of its measuring capability

In practice, pipe products are often produced. The surfaces of these components are often turned. The three-jaw chuck is often used to clamp the components for turning. It is a universal clamping fixture. The main advantage of three-jaw chuck is its high flexibility. However, its disadvantage is the inappropriate influence of the clamping forces on the geometrical accuracy of the produced components. This article deals with research of the influence of clamping forces on the roundness of turned pipes. A universal three-jaw chuck was used. The chuck was tightened using a torque wrench. The applied tighten torques were determined by monitoring the commonly used torques for a manually tightened chuck. The article presents the results of experimental research.

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.

A Fourier series is an expansion of a periodic function f(x) in terms of an infinite sum of sines and cosines. Fourier series make use of the orthogonality relationships of the sine and cosine functions. The computation and study of Fourier series are known as harmonic analysis. It is a useful way to break up an arbitrary periodic function into a set of simple terms that can be plugged in, solved individually, and then recombined to obtain the solution to the original problem or an approximation to it to whatever accuracy is desired or practical. This paper deals with the mathematical basics of Fourier series using trigonometric functions. This is the basic for a discrete Fourier transform. It allows transforming the discrete data to the frequency data or vice versa, i.e. transforming the frequency data to the discrete data. The most important part of the article is the application of the Fourier series and the Fourier transform to metrology, specifically on the roundness profile. The mathematical relationships for the practical use of harmonic analysis and the detailed method of determining the actual phase were described. General relationships do not give accurate results, due to the phase shift quadrant. The results of the harmonic analysis were applied graphically by the authors on a concrete example of a roundness profile. The individual harmonic components are shown in the linear and polar graphs as well as the resulting roundness profile. The Fourier analysis knowledge will contribute to a better analysis of the roundness profiles measured on the drawn tubes that will be investigated in the research project.

This article deals with the observation of shape and dimensional accuracy of parts after manufacturing in certain time intervals. The parts was manufactured by additive manufacturing method Fused Deposition Modeling (FDM). The shape and chosen dimension changes due to material shrinkage was observed on materials, namely Polylactic Acid (PLA) and Polyethylene Terephthalate Glycol (PET-G). These materials rank among health-conscious and usable in some medical applications. The parts were measured by using coordinate measuring machine (CMM) in certain time intervals and the shape and chosen dimensions was compared with the reference computer aided designed (CAD) model.