Create good edge flow for subsurf on a plane I have a very mesh made in a single plane that I'd like to extrude down to create thickness and add supporting geometry to use a subsurface modifier while keeping the sharp edges. The problem is I can't get a nice edge flow so the supporting geometry doesn't reach some edges. How can I fix that?



After changinging the geometry to correct the previous problem other part of the mesh gets weird, which is prone to catching light in an unwanted way:
This method will need a lot of Proximity Loops and Supporting Loops but they are necessary to keep mesh clean without glitches on sharp corners (inside K).



You can try to add to the Base Topology three modifiers. 

Solidify > Bevel (3 segments) > Subdivision surface. But this method has flaws like before mentioned glitches.