We had the discussion on PWM forum regarding painting of exhausts on the WWII era plane. I was asked about the way i would paint the exhausts. It had to be slightly rusty, dusty, well worn, and dirty.
This is my way of approaching such subject.
The plane in mention was a Spitfire, but i don't do Spitfires, and the only exhaust i could find in my stash, was the one from Bf 109 E 4.
First stage- primer. I used the Humbroll 33 Matt Black.
I got it turbo dry by spraying the Nitro mist over it, end used the hairdryer to further enhance the curing time.
Base coat of Red Brown from Tamiya.
Microscale Matt Varnish, followed by some ligh rust pigments applied with wet brush.
Then the delicate mist of hairspray, and light coat of Gun Metal.
At this stage i dumped the part under the tap for few seconds, and started rubbing it with soft brush. Some Gun Metal wore off.
Another coat of Microscale Matt Varnish, followed by hairspray, and mist of Tamiya's Buff.
Again used the wet brush under the tap to gat some paint off.
Last stage of painting the exhausts- pigments. I used the Soot for inside of the exhaust tubes, light rust imitating fresh rust, and dark rust for the old rust. Smoke here, and there and oil stains to finish the job off
Hope you enjoy.