Face Turning Octahedron

This is my FTO puzzle,i do not recomend to print it as i had to sand a lot in order to make it turn properly but it works and you can also use it to learn how to make one.
To make one,you will need to print as many pieces as the name says,since the files are named TypeOfPiece_xQuantity.stl(there is also a sticker template to print and use as a guide) You will also need 8 M3 screws.
It is the equivalent of a rex cube since a face turning octahedron is the "base" for a corner turning cube but th