This paper presents the results of a study on the dimensional accuracy analysis of models produced by 3D printing technology—Fused Filament Fabrication (FFF). Geometric measurements were conducted using a dial caliper, a 3D scanner and a coordinate measuring machine. In addition, a statistical analysis of the test results was carried out, considering the division into different numbers of test samples (3, 5, 10, 20, 30). The analysis of the test results made it possible to assess the influence of the measuring tools used and the number of samples tested on the final measurement result, as well as to determine the consequences associated with it.

The development of modern manufacturing technologies requires the adaptation of measurement methods, which generates the problem of developing a new measurement strategy and an in-depth analysis of known measurement methods. The paper presents the results of an investigation into the measurement of the surface topography of models manufactured by Material Extrusion Technology (MEX). The measurement was carried out using three optical methods: - confocal, the interferometric, focus variation. The curved surface was analysed in its central part and in the rounded area, both concave and convex. The results showed significant differences in both measurement reliability and measurement errors. The results of the research showed that interferometry was the least effective method, characterised by the highest number of non-measured points regardless of the measurement location and sample shape. In contrast, the focus variation method showed the highest number of noise - spikes/ghost points located mainly at the edges of the measured area, which has a direct impact on the calculated value of the surface parameters. On average, the differences in the number of non-measured points for interferometric measurements were roughly four and a half times greater than for the confocal method and about one and a half times greater than for the focus variation method.

The development of modern manufacturing technologies requires the adaptation of measurement methods, which generates the problem of developing a new measurement strategy and an in-depth analysis of known measurement methods. The paper presents the results of an investigation into the measurement of the surface topography of models manufactured by Material Extrusion Technology (MEX). The measurement was carried out using three optical methods: - confocal, the interferometric, focus variation. The curved surface was analysed in its central part and in the rounded area, both concave and convex. The results showed significant differences in both measurement reliability and measurement errors. The results of the research showed that interferometry was the least effective method, characterised by the highest number of non-measured points regardless of the measurement location and sample shape. In contrast, the focus variation method showed the highest number of noise - spikes/ghost points located mainly at the edges of the measured area, which has a direct impact on the calculated value of the surface parameters. On average, the differences in the number of non-measured points for interferometric measurements were roughly four and a half times greater than for the confocal method and about one and a half times greater than for the focus variation method.