Offset surface to be 3d printed

I need a set of spherical shapes offset so tthat it has thickness to be 3d printed. Does anyone know how to go about it and let me know the steps so I can do it myself in the future?surface needs thickness.3dm (1.2 MB)

The usual way is to use shell command. So Cap your shapes. As one doesn’t cap I add to extract edges, then join then close curve and then planarsrf. The I used shell with a thickeness of 1 but Shell failed !

Other solution could be for you to make inner and outer spheres. Join the inner separately from the outer. Then solid difference of the outer with a box then solid difference of this shape with inner parts.

Here I used Grasshopper to get the radius of spheres. Follow the logic, Union, Solid difference … (3.2 MB)

You can try this as well: It usually works pretty good. (what is your 3d Printing method?) if it’s extrusion based, you can usually get away with this:
1 - cap/close the object
2 - convert to mesh (Mesh->Mesh From Nurbs Object)
3 - offset mesh by some distance to add thickness
4 - export thickened mesh as obj, (most 3d print prep slicers can take an obj).

surface_needs_thickness.3dm (662.3 KB)

Correct me if I’m wrong but if you close off your object so that you have a closed polysurface, won’t the 3D printing software figure out the optimal material thickness and add any appropriate internal structures if needed to conserve material?

surface needs thickness_closed.3dm (1.3 MB)