Rapid prototyping (RP) is a supplementary additive manufacturing method to the traditional Computer Numerical Controlled (CNC) machining. The selection of the manufacturing method between RP and CNC machining is currently based on qualitative analysis and engineers’ experience. There are situations when parts can be produced using either of the methods. In such cases, cost will be the decisive factor. However, lack of a quantitative cost estimation method to guide the selection between RP and CNC machining makes the decision process difficult. This thesis proposes an automated cost estimator for CNC machining and Rapid Prototyping. Vertical CNC milling and Stereolithography Apparatus (SLA) RP technology are selected in specific, for cost modeling and process comparison. A binary questionnaire is designed to help estimate the CNC setup cost. An SLA build time estimator is implemented based on 3D systems’ SLA3500 machine. SLA post processing cost is also investigated. Based on the developed methods, a prototype software tool was created with an output to Excel chart to facilitate the selection. Five cases have been studied with the software and the predicted results are found reasonable and effective.

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This master’s thesis is focused on CNC machines. It deals with the characteristics, description, coordinates, advantages and disadvantages of the CNC machines and utilization of the CAD/CAM software. The next part of this thesis deals with the suggestion for choosing the best technology for milling slots. Milling strategy, cutting processes and cutting conditions are described in this part as well as all the issues concerning the manufacturing of the milling slots.

Diplomová práce uvádí zakladní popis ručního programování CNC strojů, jeho výhod a nevýhod, možností automatizace. Aplikace CNC obrábění na součásti, její verifikace, vyhodnocení dosažených výsledků.

This diploma thesis deals with design of the clothing storage. It is divided into two parts. In first, theoretical part was surveyed market and then produced recherche. Various materials were examined and it was decided which are most suitable for fabrication of the hanger. The hanger was designed to meet the requirements of modern times. The emphasis is mainly on simplicity and variability of use. The second part of this work is focused on the development of the clothing storage, its production on CNC, and resulting variants.

This thesis deals with the structural design of small model CNC milling machines. The work includes research modeller CNC milling machines available primarily on the Czech market, on whose basis are then selected the appropriate parameters for machine design. The thesis contains further structural calculations, selection of appropriate components, production drawings and 3D model that shows the final solution of constructed facility.

Materials which are both lighter and stronger have faced an increased demand over the past decades to fulfil the requirements across a range of industrial applications. More specifically, demands for titanium alloys have increased significantly due to its high strength to weight ratio which is particularly attractive for increasing fuel efficiency in aircrafts and cars and is also used in biomedical implants. Despite the increasing demand for titanium made products, machining titanium alloys remains a significant challenge. High material strength and hardness lead to excessive heat generation at the cutting zone which accumulates and results in high cutting temperatures due to the poor thermal conductivity. The high cutting temperatures together with inherent material properties of titanium are responsible for short tool life and poor surface finish. Despite the environmental and health drawbacks, a generous amount of cutting fluids is commonly used to control the cutting temperature in machining titanium alloys. However, conventional cutting fluids evaporate at high cutting temperatures which isolate the cutting zone by forming a vapour cushion resulting in further increases in cutting temperatures. This research investigates the effects of cryogenic cooling on machinability of Ti-6Al-4V alloy in CNC milling as compared to conventional dry and wet machining environments. Two literature reviews were conducted and a methodology has been developed and implemented consisting of three experimental stages of i) design and manufacture of a cryogenic cooling system, ii) comparative study of cryogenic cooling with dry and wet machining and iii) optimisation of cutting parameters for cryogenic machining. The major contribution of this research can be summarised as design, realisation and assessment of a novel cryogenic cooling system for CNC milling, termed cryogenic shower, which is retrofitable to an existing CNC machining centre. In addition, the research provides a thorough study on the effects of cryogenic cooling on machinability of Ti-6Al-4V alloy in comparison with dry and wet machining. The studies range from power consumption and tool wear through to surface topography and surface integrity. Furthermore, the optimum cutting parameters for cryogenic machining are identified. The research demonstrates that using the cryogenic shower has significantly improved machinability of Ti-6Al-4V through realisation of higher material removal rates, reduced tool wear and improved surface finish, surface topography and surface integrity.