The thesis continue thematically in the previous development of the wax mixtures for the company Fimes. The general description of the investment casting process from the production of the die to casting of the wax pattern is handled in the first part. It is followed by the summary of the previously carried out experiments on cracking the shells. The experimental part describes the individual operations from the production of tested wax patterns to casting in the Boilercláv. The newly developed wax mixture is compared to the wax mixture used by the company Fimes. The experiments focus on the possibility of cracking the shells during the casting process and the dimensional stability of wax mixtures.

This thesis is to evaluate currently used wax and compare its properties with of newly purchased one. Further, it is to evaluate whether the quality is reflected by using "boiled wax'', which is being used as a runner wax. All tests were carried out at the Fimes a. s. In the first part of this thesis, there is a brief description of the lost wax method. This is followed by a decription of wax blends from technology point of view. The experimental part describes the operations from the production of wax patterns, through their dimensional inspection, up until dewaxing process. All the results are noted and compared.

The main target of this thesis is to choose the suitable hard filled wax for the invest-ment casting foundry Fimes a.s. There are several suppliers of these waxes in the World and in this work waxes of the most reputable suppliers from Europe have been investigated. During these tests there were mainly technological properties of the waxes and also dimensions of both wax patterns and also the final castings measu-red. Suitability of the tested waxes, their technological characteristics, analysis of di-mensions and finally basic economical calculations have been then used in this the-sis as a tool for the recommendation for the most suitable wax for the Fimes foundry.