Accuracy of Geometry of Plastic Gear Produced with 3D Printing Technology

The article concerns the accuracy of the geometry of a single-stage gear made of plastic with 3D printing technology. The aim of the paper has been to assess the accuracy of gears made by 3D printing methods. The accuracy assessment has been made in relation to the accuracy of the same steel gears made by machining. Gear virtual solid models, necessary for using 3D printing technology, have been created based on steel gear using Reverse Engineering Technique. Plastic gears have been printed with two 3D Printing methods: Selective Laser Sintering (SLS) and Multi Jet Modeling (MJM) from plastics used in these methods. Gear geometry has been measured using a measuring machine. In order to determine the manufacturing accuracy, the accuracy classes of the geometrical parameters of gear have been used. It has been found out that the manufacturing accuracy for both 3D Printing technology methods is similar but worse than for machining. The obtained results of gears accuracy made by SLS and MJM methods correspond to the International Tolerance (IT) grade 12 or higher. Milling process produce the IT grades indicated. The originality of the work is the study of the accuracy of gears geometry made using two different 3D printing methods. The test results obtained are the basis for conducting research on the impact of individual parameters of 3D printing technology on gears accuracy.