thanks!
i’m looking for the tutorial now, since it’s my lunchbreak 
You’ve got some decent generic dirt going now, but I think it’s time you stop faffing around trying to get these textures to magically make realistic dirt for you 
It’s time to paint your own textures, or at least masks for these generic dirt stuffs.
Dirt likes to accumulate in concave corners and crevices (which is why dirty vertex paint and an AO bake are a great starting point), but remember that it also gets rubbed off in places like convex corners and large smooth/flat areas.
Nothing beats painting these maps yourself, but if you’re as lazy as I am, you can often get away with just an AO and a scratch map.
I recorded a tutorial of sorts a while ago on my workflow - http://www.youtube.com/watch?v=KGeJAFSlbRU - it’s for cycles but the same principles apply for any render engine. I just like the interactivity you get from a viewport render in cycles as well as how logical node-based materials and textures are.
@gregzaal i take it you’re talking about the dirt/scratches on the wood?
i’m currently using the dirty vertex paint for doing the scuffing on the metal.
i used the texture painting to create a black & white mask before (the pics with the chipped paint) but this dirty vertex painting really gives a better and more realistic result!
anyway, i will deffinitely check out your tutorial, i watched a part of it but i don’t have sound here so… 
here is a little update on the metal part (still working on it)
@craig Jones: Thanks a lot for the info! new doors are opening for me!
Very welcome, I am glad to help! lOok ing much better now, closer to the effect Anthony C showed with his references
Yeah, now you are getting somewhere, really taking shape now. :yes:
here is the result!
i used the dirty vertex painting as a mask for all the textures and for the glossiness.
Thanks to everyone for their amazing feedback and tips + tutorials!
Much nicer result, and especially if you look at it compared side to side with your original render - this looks really cool!
Congrats!!! And thank you for this thread, to you SatoMibu and all the people who fed you back! This was most usefull to me!
@Craig Jones: thanks! ^^
@Sakrecoer: thank you! And i’m not really sure what i did to help, but you’re welcome 