There are two parts. There is the sieve structure and the mesh. You can print different sized meshes and quickly switch them out from the sieve housing if you so choose. The sieve is designed to interface with standard small sieves (3 inches in diameter). You can then put your desired combination of sieves on a shaker stand and perform a soil analysis.

The two openscad files can easily be edited. The sieve_structure file should only be edited to change the text on the cylinder wall that indicates what size mesh is being used. The mesh file should be changed modify the size of the holes in the mesh.