V diplomskem delu smo s programom Solidworks zasnovali 3D-vpenjalne priprave za vpenjanje ojnic. Od odkovka ojnice do končnega izdelka smo si zamislili dve vmesni CNC-obdelavi. Za prvo CNC-obdelavo smo izdelali dva različna 3D-modela vpenjalnih priprav in jih med seboj primerjali. Za drugo CNC-obdelavo smo izdelali en 3D-model vpenjalne priprave. Prednostne naloge vpenjalne priprave so bile, da obdelovanec med obdelavo povsem fiksira, cenovna ugodnost, obratovalna zanesljivost, enostavna zamenjava deformiranih oziroma obrabljenih delov. Standardne dele vpenjalnih priprav smo izbrali iz spletnega kataloga Halder.For this bachelor’s thesis, we used the Solidworks software to design 3D clamping jigs for clamping of connecting rods. From the forging of the connecting rod to the final product, we conceived two intermediate CNC machining procedures. For the first CNC machining, we created two different 3D models of clamping jigs and compared them with each other. For the second CNC machining, we made one 3D model of the clamping jig. The priorities of the clamping jig were to fix the workpiece perfectly during the machining, achieving cost-effectiveness and operational reliability, as well as easy replacement of deformed or damaged parts. The standard parts of the clamping jigs were selected from an online catalogue by Halder