This is older, but one of my favorites. I need to revisit this. 
Where it came from, but it's my work: https://www.thingiverse.com/thing:3357545

I recently received a commission to re-cover some jewelry displays. Rather than simply re-cover the existing pieces, I chose to also design 3d printable replacements. In this video I describe the problem, and show the files. In the next video, I'll show how to cover the 3d printed parts with your choice of leather or fabric. If you're interested in purchasing a finished product, please contact me via and I can see what can be arranged.

Necklace Neck Part 1: https://youtu.be/wUDHMASt1_I
Necklace Neck Part 2: https://youtu.be/kXmFO1MlB1k

If you're going to buy leather for this project, I always buy my leather from Springfield Leather. Look for their lamb skin.