Solidify modifier for reducing 3D printing cost (make model hollow)

My task is quite simple: I want to make generic models hollow for 3D printing them on Shapeways.
So far I do this using my own inaccurate voxel-based algorithm. But it looks like that Solidify almost does what I want, but with some issues.

Consider this mesh:
sample.zip (1.05 MB)

There are some quite thin parts on collar and ears and solidify does not work on them.
Following picture should illustrate what I mean:

http://s27.postimg.org/q7ld8u1dv/image.jpg

Is there an algorithm in Blender that can do what I want in this case? Or another tool?
Sorry for my shitty Paint drawings :slight_smile:

Little planning and work flow can solve that problem. First create the main body where cavity is located. Solidify and apply it. Now, work on the outer detail by extruding them from surface.

Skin modifier might be the way to go. Sketch out a basic shape inside the bust, tweak in edit mode by moving vertices around with proportional editing to get the thickness you’re after, then use boolean modifier when you’re satisfied. Here’s a blend where I did the sketching step.

…And just to make sure the idea is sound, I followed through. Here’s the finished product.