Complex object consisting of multiple partly overlapping shapes, blend together to keep one outer shell Ok, so i've converted hair particles to a mesh and gave them a thickness (i think it was with solidify). Anyway, the object is now too complex (i want to 3D print it). So i just want the outer mesh detail, and everything inside should be blend together, with no more individual features but as one solid shape.

Basically, i'm looking to do in 3D in Blender, what is very easy to do in 2D in Illustrator with the "unite" option in the pathfinder tool. Like this:
https://www.youtube.com/watch?v=Fg95K3NAtSM

I tried with wrapping something over it and applying that modifier, but that wasn't nearly accurate enough, even after many subdivisions.

I tried with bolean, but that didn't work either. That might work if i applied each shape individually but there are thousands of shapes, so this is not an option.

It's a feature is often missed in Blender before as well. So i hope something like the Illustrator function actually does exist.
I found out, that applying a union boolean on an exact copy in the exact same location actually does what i'm looking for... but it wouldn't do it on the hair i had (i used screw and solidify). So, i went back to the original file, i removed all children particles, converted the particles to mesh, and then selected all, and extruded them for width, and selected all again, to extrude them for depth. After joining this mesh with the body and head, i COULD make a duplicate and perform the boolean union on the entire object. 

For now, the solution will have to do. But i still can't understand there is no simpler way to do this. Mindboggling actually.