I have not used this with structures, just rolling stock, but in some instances where I think I over-weathered, I carefully apply chalks or pastels close to the "original" color, which at least tones down the overweathering to an extent.
Dave Nelson
The lesson here is that with weathering, it's a lot easier to put more on than to take some off. Weather lightly to start, then keep adding. When it looks right to your eye, stop.
Untill you seal it the wash can be removed with alcohol to some extent, once sealed you start over.
I typically use a mixture of water and drywall compound for mortar on brick walls and remove with paper towel until I'm happy. I then use charcoal sticks from the art supply store which is removable if I'm not happy with it.
I guess if I didn't like it, I'd repaint it all, but material texture wouldnt be all that crisp.
Finding an easily repeatable process that yields neutral / minor weathering is the safest route unless you're going for a factory covered in heavy soot and rust then it's pretty much no undoing that.
I've found that removing and wiping previously applied weathering with alcohol is an effective way to enhance the look. It takes practice to remove the material without it obviously looking like it's been wiped off. Its become part of my weathering technique.
Grabbing a little bit of the underpaint is okay, since it changes the finish and the tone of the spot that's been wiped, like real weathering might look....less uniform. Of course, removing a lot of it is not desirable.
Usually the first application of alcohol and wiping (keeping it wet with water...wiping with a wet cloth or paint brush.. as to not have it dry too fast) is usually not a problem. If you have to keep applying alcohol to the project it starts to get to the point where it looks worse than what you started from. My experience.
- Douglas
From my early efforts at weathering, I realized I was going much to heavy. I cut it back to much lighter effects, and I usually use powders now. This lets me place a structure and look at it on the layout before sealing it, so I can easily go back and re-do it if necessary. Even after I seal anything done with powders, I can go back and add more.
It takes an iron man to play with a toy iron horse.
If you sprayed the building with flat finish to seal in the paint before weathering, you may be able to use straight alcohol to remove at least some of the weathering without taking up the underlying color of the building. Otherwise, if you can find a weathering chalk or powder that is the color of the building (or a touch lighter) you could apply that over the weathering to lighten it a bit.
Of course, everything doesn't have to be weathered the same. An old, dirty building could be part of the same complex as a newer building, or next to an old structure recently repainted. Could be having different structures weathered to different degrees might look more realistic.
I don't model specific buildings or trains so I have a lot of leaway in how things turn out. I have gotten pretty good at the mud for mortar technique but it is always a roll of the dice in the final look.
I recently did the Walthers Industrial Office in a light color and planned to use it in my refinery. At the last step I wound up making much more heavily weathered than I intended with the alcohol/india ink wash.
I can use it as is but I will need to weather everything in the refinery a heavier than I had planned so it doesn't look out of place. I'm not sure which would be better - starting over with the office or doing the whole refinery heavier than planned.
How often do you start over on a building (or scene) that doesn't come out as planned?
Rick