Thanks ctbram
Have not had a lot of time today to do much more, yes a bump map on the rust and were the paint has come of if done right will bring it to life, I must admit that if you know what effect you need you can find most for free on the net, Once I have finish this I promise to do a tutorial then I can get back to my tank still looking for a good scale ref for the M151 weapons system......LOL
Thing to do
Finish of metal
Dirt map
Bump map
Final gather render (never done one but looks easy)........dave