Much like red barns or wood-framed houses, concrete silos are a classic staple of the American landscape. They can be seen from the Atlantic to the Pacific, from the great plains to the industrial northeast. Used for storing diverse materials ranging from concrete to grain, these industrial pillars can often be found alongside railroads, making them an important feature on many North American layouts. In this article, we’re exploring how to give consumer plastic silo kits a realistic textured concrete appearance.
Before any detailing or weathering can be done, your kit will need to be assembled. We’ve chosen the popular Walthers Medusa Cement kit as the basis for this project. This kit can be found in both HO and N scale, and the following steps can be applied to either scale.
The kit comes pre-molded in a selection of appropriate color tones, however we’ve decided to go a little lighter on the base color for the silos. This will allow for more flexibility when weathering the painted model. For the base coat, we’re using Mission Models Radome Tan, mixed with aircraft gray, and a little bit of white. Once you have your preferred color tone mixed, it’s time to start applying it to the model. While painting, make sure to use broad strokes from side to side where possible. This will help the overall appearance of the weathering job, as it will create a similar linear texture to the cast concrete seen on the prototypes. Once our base coat has dried, we’ll need to go over with a second layer. Make sure to again use broad, side to side strokes.
Once the silos have been fully painted, we’ll move over to the attached corrugated loading shed. There’s not a lot that needs to be done with this, as the pre-applied Walthers coloring definitely looks the part. However it can be enhanced with a thin layer of silver textured acrylic to give it a metallic shine. This can usually be found at your local craft store.
Once all paint has dried, it’s time to begin the weathering process. We’re using a range of PanPastel colors from their Rust/Earth, and Gray/Grime/Soot ranges. Before attempting the more noticeable detail, it’s a good idea to apply to areas where dirt would naturally collect. We’re using tones from the Rust/Earth range for these areas, which include the seams between the silos, and the tops and bases. The deeper the area for dirt to collect, the heavier the powder should be applied. For the tops and bases, we’re using a typical artists paint brush to run a thin line around the silo. Once this is applied, we’ll use either a finger or a paper towel to spread the grime appropriately.
This is the step where your silo might start looking a little strange, and that’s totally ok. We’re not done yet! Once all the nooks and crannies have been weathered to your liking, it’s time to move on to the main weathering process. Many prototype silos have accrued “rings” of various grades of grime and weathering due to years of being exposed to the elements. This is what we’ll attempt to recreate in this step. We’ll start with several rings of rust/earth tones. These should be a little lighter, as the more noticeable colors on the prototype are generally darker and closer to gray tones. We’re going one silo at a time, however it’s important to maintain roughly the same lines across all silos for the correct appearance. After applying the rust/earth lines, come back with your gray/grime/soot tones. You can use a variety of these to create different textures as you work your way down the silos. These rings should be more pronounced than the rust/earth tones.
Now that all rings and lines have been applied to your liking, it’s time to blend them into the structure. Using a combination of white and light gray, gently dry wash the silos with these tones, ideally with a broader brush, from top to bottom. This will not only help to blend your rings into the concrete texture, but will also create a realistic top-to-bottom texture flow. Once this has been completed to your liking on each silo, the final step is to add some “streaks” down the side of the structure for added realism. We used a mid-tone gray for these, and applied them with the same “hands on” approach as in Step Four.
For the finishing touch, some rust and dirt streaks can be added to the corrugated loading shed at your discretion. At this point, your newly weathered cement plant or silo will be ready to add to your layout!