tunnel portal weathering

[streettrains]

was lucky enough yestarday to find a HO replica of the Hoosac tunnel portal...
was wondering if I could get some tips on what I could use to really weather it up...

thanks

Mike

[selector]

I am unfamiliar with the prototype, so take what I suggest with some consideration.

If it is concrete, paint it a mix of medium gray and a drop of 'cinammon' and a drop of a bright yellow. Or , just a blend of greys. Then, a light wash of very light earthen colour dripped here and there. Let dry. Then apply a series of India Ink washes, maybe three or four of them, letting each dry. That should do it. Don't forget to use a heavier wash right over the tracks, fanned out and upward to simulate the exhaust residue.

If it is wooden, paint it a mix of 'burnt umber', some medium grey, and 'cinammon'. When dry, apply a heavy black wash several times to bring out detail and to darken it as if it were creosoted. Lastly, don't forget to make your smoke deposits over the centre area.

Sort of like this: