The objective of this article is to make the design and the validation of a solar mill for rural use. Based on the operating principle of the solar hammer mill, a transmission tree was being created, modeled and dimensioned. The tree behavior is obtained by analyzing its operation in all cases of possible load. The design and dimensioning were carried out based on analytical and empirical equations such as the ASME code. Five diameters (8 mm, 15 mm, 25 mm, 35 mm and 50 mm) wereevaluated according to different types of materials. The evaluation of the type of tree materials has optimized its weight from 40% to 70%.CATIA logical via the method by Finite Element Analysis was used to construct the three-dimensional model and realize the dynamic simulation of the mechanism. The optimal choice of diameter 25 mm of material 4 CD 16 was made because of a good compromise of resistance-weight. These results indicate that the maximum equivalent von Mises stress is of the order 39.4 MPa with a maximum value of the static deformation is of the order of 1.25 E-02 mm.