Very nice work, I like the designs and the textures, I too like to play with cogs , my phones lock screen is all cogs lol
I was reading through the comments, and would like to thank Nitenurse for referring to my image, and yes it is in the Abstract forum.
A great improvement to the shadow, but you miss it on the large cog casting form the arm, it was there at the first image, but not on the last one.
You have mentioned as something like swirls on the sun gear, do you meat as a texture?