## 3 Results
It should be noted that in these figures, the printer has difficulty generating precise angles. In Figure 5d, we can see the best results indicated in positive shapes that correspond to the hexagon circumscribed in a circumference of 2 mm in diameter and a triangle circumscribed in a circumference of 1 mm. In Figure 5e, we can see the results of greater precision of the whole test that correspond to the positive circular shape of 0.6 mm in diameter whose actual print measurement is 0.62 mm. Likewise, we can observe the best of the resolutions in a square shape that corresponds to 0.6 mm on each side. Figure 4: Images of the print test (Ameralabs Town) made at 30\(\times\). (**a**) Surface textures, (**b**) “Alternating deepening plates” test, (**c**) “Cross-shaped bridges” test, (**d**) Minimum width of the opening” and “Minimum Height of the opening” test. These results at first glance do not seem very encouraging. However, as suggested by the creators of the Ameralabs test, it should be mentioned that the result of this type of test depends on the properties of the material as well as the concentration of pigment in the resin. If one uses under-pigmented resin, it is highly possible that due to serious light scattering and light bleeding, just a few or none of the ledges will be formed. Therefore, these results are subject to improvement. The technical specifications of the \"Wanhao Water Washable UV Resin\" used for these two tests are: Ash \(<\) 0.2%, Shore Hardness 75D, Experimental Shrink 3.3%, Uncolored Reactivity 423 mJ/cm, Viscosity @ 20 \({}^{\circ}\)C: 90 CP, Density @ 25 \({}^{\circ}\)C: 1.1 g/cm, Acidity \(<\) 0.31 mg KOH/g, Water Content \(<\) 0.23%, Surface Tension 36.5 Dynes/cm, Tensile Strength 9100 PSI, 6% Elongation, and Glass Transition Temperature 104 \({}^{\circ}\)C. Future tests can be improved by changing print settings and using resins with different properties. After the calibration, a functional test was performed to determine its real resolution and to be able to compare it with the resolution estimated in Section 2.1. This aspect is important, since the final objective of this printer is to be able to be used in the artistic field for the manufacture of micro-sculptures, that is, for pieces smaller than 20 mm. Therefore, first, the minimum size of the printable parts was checked while maintaining an adequate level of detail. In Figure 6, you can see the different prints from a size of 30 mm to a size of 5 mm in height. It is important to note that all FDM printers and many low-cost DLP printers have trouble printing parts that are 5 mm in size. For these sizes, the result is usually a printing error, since the PLA or resin cannot be deposited correctly and the figure is unusable. It is important to note that one of the objectives of the 3D printer is to register the maximum detail of the figures, even in the smallest figures. To check that the level of detail is maintained in all print sizes, a measurement of the ear length of the model used has been made. In the smallest model (5 mm) the length is 1.317 mm (Figure 7a). It is estimated that below this measure, the quality of the details is lost. In the largest of the models the length of the ear is 7.949 mm (Figure 7e). Figure 5: Calibration test results for XY axes. made at 25\(\times\). (**a**) Designed test, (**b**) best result for square and circular negative shapes (**c**) best results in triangular and hexagonal negative shapes, (**d**) best results for hexagonal and triangular positive shapes, (**e**) best results for square and circular positive shapes. To measure the resolution in the z axis, a Dino-Lite microscope with up to 240 magnification has been used where the thickness of each layer can be measured. In Figure 8, we can see, with 200 increases, the results obtained in 10 measurements carried out randomly in the sample. As can be seen, the thickness of each layer presents a certain variability due to the tolerances in the repetitive movements of the z axis. The values obtained range between 17.942 microns and 24.670 microns.