I can work on this model only few weeks a year, but everytime I add always something new to it! This time I "weather" it in order to give it a more realistic look and I paint some additional details.
The oil filters are a classic of the weathering! In particular with the "dots" technique one can achieve a more lively color out an otherwise flat base.
The technique is always the same: small dots of oil colors, light ones (red, yellow) in the center and dark ones (green, navy blue) in the borders and in the shadows. Then, using a flat brush soaked with turpentine, spread them (with up-down strokes on vertical panels, circular ones on horizontal surfaces) and blend them with the background, without wiping them out completely!
The result is barely visible but nonetheless you can notice the difference!
First I painted the edges of the road wheels with a steel color, simulating the bare metal that rolls and wears on the tracks. I used an excellent Model Master enamel.
Then I mixed equal parts of Russian Earth and Fresh Mud pigments by Mig, I added turpentine and I brushed the mix on the inner wall of the running gear.
While the mix was still damp, I dabbed it with dry pigments, the same of before.
The tracks were colored as shown in this post and they were eventually assembled.
I applied the washes on a clear gloss coat, using a van Dyck Brown oil color diluted about 60% with turpentine. They considerabiliy emphasized the details.
Moreover, I applied another wash in Mars black on the grids of the engine air intake, thus giving them a sense of depth.
The dry-brush helps to further highlight the protruding parts. In this case I used a reddish Naples yellow oil color, rubbed in extremely small quantities with an old paintbrush.