I was bored a while ago, so I made this model. The chains used path deform to bend interestingly. Blender 2.40, ambient occlusion, raytracing- render time of 30 mins or so.
The chain is floating?! :o magic?
Looks good to me. The individual edges of the round part of the lock are slightly visible but not badly. Nice work.
edit: Guess I didn’t look at the chain very carefully, it’s floating like everyone’s saying.
Very nice pic, modelling is good, there’s just a little remark: the last ring of the chain is horizontal, it’s abnormal (you forgot the gravity…). 
everything is pretty good, but none of the links are touching each other. I think that usually happend with chain. If they are loose enough to not have to touch at thier interlocking ends then they will fall a few degrees off 90 and touch there, but they will touch.
the texture on the chain is not right. chain is either shiney and not blackish, or matte and dull. yours seems to be a combination.
gravity sucks
Thanks for all the comments, I’ve worked on the floating chain issue (attached image). Any details on changing the material?
Attachments
The parts of the chain cannot be completely perpendicular one to each other. They have to lie on the floor and they are like “sustained” by something.
yes yours looks to perfectly patterned. chain when laying flat is pretty much random.
dont know about the material without knowing your settings on it,.
Maybe it’s just me, but the cahin on the right’s first link sort of looks like its going through the padlocks bar. :-?
To me, the ambient occlusion makes the picture look dull-as-toast. There are no significant specular-highlights anywhere! If it were me, I’d nuke the AO (and all the time that goes bye-bye with it!) and set up a nice, simple, three-point lighting setup with different (soft) colors on each light.
Right now, at least on my screen, the center-knob of the dial is simply “not there.”
I can’t fault the modeling at all – didn’t inspect the chain too closely – but the presentation is … lifeless.