I bent the fame and hangers after heating it up with a hairdryer. That works quite good and you get a nice front surface. Put in the lenses before, the frame will shrink perfectly to them!
I connected the hangers to the frame simply with tiny nuts and bolts. If the holes are not printed well enough, just drill it. ;-)
Frame looks a bit thick. I'm still working on it.
The author hasn't provided the model origin yet.