Model Railroading > Weathering experts

On E units with Farr grilles,the grilles cover
car body as well as air intake openings.Over a
period of time the grilles get dirty at these
openings and really stand out.
How would you model this detail on HO locomotives?

Uncle Joe
Seffner,Fl.

Do you have any pictures to show exactly what you're referring to?

Thanks,
- Jeff Carlson

retcsxcfm Wrote:
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> On E units with Farr grilles,the grilles cover
> car body as well as air intake openings.Over a
> period of time the grilles get dirty at these
> openings and really stand out.
> How would you model this detail on HO
> locomotives?
>
> Uncle Joe
> Seffner,Fl.

First mask for the entire grill and give it a light coat of your preferred color. Carefully q-tip the paint off the raised areas to define "grillness." Then carefully mask over the body areas with good tape like Tamiya. Followed by another coat of your weathering color. Wipe off the mesh. If you are clear as to where the inner carbody frame pieces are located mask them. A third spritz and wipe should leave you an interesting grill. Note, the paint must go on thin, dry and dilute so that it doesn't creep under the tape which is laid over mesh.

An alternative is to do the same masking but use dry materials - pigment, pastels and so on. This has an advantage of being easily washed off if you aren't pleased. The downside is that it is harder to layer dry materials.

Quick crop of low-hanging fruit (the pic file was open)... I'm sure there are a hundred pics that will show more.

This is a unit that got washed relatively regularly. With some more advanced neglect, the oily crud tends to pool at the bottom of the lower row of louvers. It's barely gotten started here, but you can see the trend.

What I've observed in pondering this exact question is that the horizontal strips stay relatively clean and free of the greasy dirt -- it's the louvers that schmutz up, mostly. I think this may respond best to a careful masking job and a bit of airbrush work. I'd use a brownish wash, not dead flat and probably with a hint of gloss, after masking the horizontal middle dividers carefully. Slow, light passes, slow buildup, see how it goes and don't try doing it all at once.

There's some fuzzing and indistinct bordering to the prototype's patterns, and I've considered either doing a close finish pass with a tiny airbrush orifice at low pressure to fog the edges of the masked rectangles... or maybe brushing carefully to blend. I've also considered chalks with masking. 

The one concern that I'd have is that model grilles are etched with perforations, where the full-size grilles are stamped with louvered openings; the full-size dirt catches in the edges of those openings, and it's going to be harder to replicate that if you wipe off the paint from the stainless surface of a model grille -- you'd be removing half of what you want to retain. I think the key may be to thin the wash, and leave the area over the openings to cover the model's "slats" but not obscure them with opacity. And by masking the horizontal dividers, there's still some brightwork and definition.

A spare shell and some prototype photo study will reveal where to apply the effect. So that's the theory, anyhow, in 5000 words or less. Time to try it out.

Sidebar: in the Olden Days Before RPM, I just shadow-painted the backing on the shell -- light gray patches for the clean areas, dark brownish black with a hint of yellow for the schmutzy blocks. It worked at three feet like gangbusters -- the perforations in the stainless grille etchings let the backing colors show through, and the resulting light-and-dark patches were illusory... but tended to fool the eye. Plus it's massively easier than all that masking, and everything else about the other techniques offered!

~ BZ



Edited 1 time(s). Last edit at 04/26/17 02:17 by Notch16.

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Thanks for all the replies.The last one is the best
and shows a picture.

UJ

India ink or Vallejo wash, flat brush, vertical strokes.

Jim