The process of injection moulding is usually used only for the production of large batches, due to the high cost of tools. Low cost of tools, made by alternative manufacturing technologies, make production possible for small batches. Following master’s thesis presents an analysis of stereolithography-made tool insert, when injecting polypropylene and acrylonitrile-butadiene-styrene. From the wide range of available materials, we have determined the most suitable one, based on the known load conditions. Unknown mechanical properties were determined using a compression test. Obtained material properties were used in the strength analysis, where the limit values of the injection moulding process parameters were determined. Surface and geometric errors of the printed tool were eliminated by changing the print orientation and correcting the CAD model. We carried out 70 injection cycles before the polymer tool broke down. After each cycle, we monitored the temperature on the tool surface and detected minimal effect of cooling, as a result of poor thermal conductivity of the tool material. Poor thermal conductivity resulted in heat accumulation, decrease of mechanical properties and deformation of tool shape. As a result, additional stress formed in the tool and caused it to break.
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