making an intersecting curve manifold i am using blender to make files for digital fabrication , 3D printing and CNC milling . i am working a little project where i have been sketching with beveled curve , my problem is that when the curve intersects the mesh also interects and i need it as a solid object with no interal vertex . does anyone know a good solution to this problem . i have been just trying to stitch it back together myself but it is time consuming and not great results . 

many thanks
You can try to keep only a quarter of it so that you can clean it "by inside" and then apply a mirror in order to obtain the whole shape again.



The blend here : http://www.pasteall.org/blend/42115