Improving render quality in Cycles?

From the information I’ve been able to gather I rendered a hex bolt, using the Bolt Factory Add On.

  • I used the Edge split modifier with default settings
  • set the mesh to smooth
  • marked the edges at the top, where the key goes in, to be sharp
  • I used environment lighting and a shiny material, with a roughness of about 0.15
  • I did try a subsurf modifier, but it kakked up the hexagonal part of the mesh

On the last point I could split this to a seperate mesh I suppose.
Anyway, how can I improve this approach? Any thoughts are much appreciated.

Still can’t work out how to put an image in the post.

looks good to me

unless you need a shiny one !

looks like some Durium bolts for connector !LOL