Old concrete is one of those elements in the landscape that can be frustrating to model. Getting the texture right is fairly simple using cast plaster as the two materials have very similar characteristics. Getting the coloring right is another matter.

Old Concrete

As seen here, concrete weathers to a wide range of colors and textures. Water and freezing temps will cause the surface layers to flake off, or spall, revealing the aggregate underneath. Rust from attached metal work adds stains and streaks and, atmospheric dirt and other particles will imbed themselves into the surface such as seen on this old station platform in West Harrison IN (below). Of course drippings from oil and fuels or other liquids will stain and discolor concrete in myriad ways.

Old Concrete_000

As you can see from the truck docks in the first photo and this equipment box near Valley Junction (below), horizontal and vertical surfaces will weather differently depending on their exposure to the elements. Old concrete_001

Making progress
Last week, I redid the casting for an old foundation that will be included as part of a remake of the scenery around the Mill Track. Here’s where things stand so far.

Robert's Mill casting painted and weathered

I colored the raw plaster with craft paint using a witch’s brew of colors in a vain attempt to reproduce the color of old concrete. Let’s just say I didn’t come close to what I wanted. That’s why I’m not going into great detail on the colors used. Color is very subjective, as we each see it differently. The process is also complicated by the fact that we try to match a color seen outdoors under intense full spectrum lighting to a color viewed indoors under much weaker light, even if it is labelled as full spectrum. Furthermore, color matching has never been a strength of mine in spite of many years of trying.

The craft paint was only doing a marginal job, so in a nothing-to-lose frame of mind, I took a clean brush and started to apply some MIG weathering powder, Industrial City Dirt to be exact. This showed promise as it killed the unnatural plastic look of the craft paint and also added that ground-in dirt appearance the paint color alone lacked. A similar technique I’ve used with good results is rubbing on plain dirt. As with the weathering powders, it kills any sheen and gives a hint of natural color that helps tie everything together in a scene. To see how it would look, I placed it in position temporarily. This gives you an idea of how it will relate to the existing mill building from Cedar Grove (below).

Robert's Mill casting in place.

The full-size foundation has hints of moss and mildew on the interior walls close to the ground where moisture lingers. Some more weathering powder, in a green shade this time rendered that effect nicely. You may be able to see it in the close-up photo.

I hasten to add that this is just the beginning of the modeling. All I’ve done so far is color the foundation walls and add basic ground cover. There is more vegetation and trees to come, disguising the seams around the base and adding a photo backdrop. All of that will be detailed in the next volume of The Missing Conversation.

Regards,
Mike