The following project has the intention and purpose to explain and compare the different types of cantilever of different projects to find an economical solution and, have the possibility to unify all of them. Once done, the comparative study will be explained in a new design of cantilever with the intention: Reduce the weight, reduce the price and unify the assembly. First of all, it’s been realized an exhaustive study of cantilevers that exists in market. Once done, has continued with the study of materials used, types of unions and assembly techniques. The first thing that has been done is investigate in different cantilevers and take all of the necessary information related with all of the features designated previously. Then, it’s been removable the parts that are directly related the addressed issue to realize a perfect report. To find the success with this comparative report and could get a perfect result, being conscious of the better result in the comparative study, it’s been realized a study from the norms and technical specifications to know the partialities and delimitations that the customer wish have in the cantilevers that are going to be mounted in their train. All of this information has been removable from the compilation of norms and technical specifications that the customer has facilitated us to inspect and create the new design from the imposed by him. In this report have been included all of documents to confirm all of the information written in this report. Finally have been realized an economical study of viability of new structural element to define the costs of first period and the profitability of new design. Simultaneously it has been conducted annexes where are expansion of information and some details with corresponding calculations.