Is it possible to expand / separate components of a 3D object?

Are you logo 3d object or decal(Bitmap)?

Hello with infos of the model or a picture it's difficult to understand but i think that could help.

1 - clic on the magic wand tool and set the selection size. 

After you can select the side you want and apply a color or a meterial and on the right panel you can adjust properties of each colors or materials

Hope that will help