Shameful, shameful drafting skills

I can draw.  Perhaps I'm not the best in the world, neither am I the worst (see examples here)  So imagine my dismay this morning when I tried to draw a simple ring design for a customer.

These are my pathetic attempts (not including the multiple mistakes that I erased) before I finally got it right:

And finally, a mixed success.  I need to practice drawing jewelry from life, I think.  It's pretty hard to visualize without a real life reference.  Lots of geomtry going on and not at all free form like my everyday sketching.  Normally I just sketch to keep ideas in mind just for myself, trying to express an idea to someone else, someone who doesn't really understand jewelry, is much, much harder.