Summary

1/Find a mesh that you wish convert to a wireframel, for example a mathematical surface from https://www.google.fr/search?q=MATHS+SURFACES+MESH+MODELS

2/load the surface in blender. if it is .wrl, you can try to open it in meshlab and save as OBJ first

3/in "object mode" search the right menu for the spanner>modifiers>wireframe modifier

4/export the object with desired settings

5/if necessary, use Netfabb to correct manifold errors that seem to happen 50% of the time from the blender plugin.

You can also bevel the model in blender and try other modifiers. Please post your findings here.

Blender tips:

To fatten up an object, Alt+S in edit mode, with the object selected (press A to toggle select the entire object). Alt.S is shrink-fatten, vertex extruding.

https://www.youtube.com/watch?v=_APvFlwCHfE

I wasted time with trying low poly sheep meshes from sketchup warehouse, all the faces have to be roughly the same sizes, else it results in reverse polygons, also there are sheep models with mismatched vertices which also make messed up results, so use watertight vertices and top quality starting mesh.

-=Freeware Programs List=-

Blender 64 (difficult program but it takes 3 clicks to save a wireframe conversion)
Netfabb (mesh mending program free version or oldapps.com version)
Meshlab (swiss army knife mesh program, loads saves all formats)
meshmixer