Cement Hopper Weathering Project

I wanted to try simulating caked-on cement that typically accumulates on the roofs of cement hoppers. My choice of material was chinchilla dust mixed with weathering powders.

Chinchilla dust was discussed in an earlier message post on Model Railroads of Southern California:

https://groups.io/g/ModelRailroadsofSoCalif/message/15090?p=,,,20,0,0,0::Created,,chinchilla,20,2,0,69402132

The car for this project was a Bowser HO scale two-bay covered hopper built from a kit. I gave the car a coat of Tamiya TS-80 flat clear sealer and then applied PanPastel gray media (Neutral Grey and Payne's Grey Tint). I followed this with another coast of Tamiya TS-80 flat clear sealer. This was the base for the cement weathering.

To make the imitation cement I mixed two parts white weathering powder with one part dark gray weathering powder and one part chinchilla dust. After thoroughly dry mixing these I added 91 percent isopropyl alcohol to make a liquid with the consistency of milk. Be aware that the liquid is much darker than the resulting dry finish.

I applied this liquid to the top and sides of the car and allowed it to dry. When dry I applied a second coat to the car roof.

When the second coat was dry I used a stiff brush to remove excess material, being careful to use light, gentle strokes.

When I was satisfied with the appearance of the car I gave it a sealing spray of Tamiya TS-80 flat clear sealer.

The simulated cement on the car roof is more grainy than would be seen on a prototype car but the exaggeration is for effect. This is nothing unusual as in this hobby we have exaggerated rivets, even high-end cars, as well as exaggerated wood grain on cars and structures. It's all for effect.

Corrugated Pipe Load Project

This was another HO scale open car load project. The corrugated pipe load came from Grain Belt Models, available on the Iowa Scaled Engineering website:

https://www.iascaled.com/store/GBM

All I did to the pipes was ream the ends to achieve a thinner, more prototypical cross section, prime and paint them. I then glued the pipes together in rows of three, attached to crosswise wood supports with space allowed for vertical spacers to be added later. The rows were then glued together with the vertical spacers added.

The car was an InterMountain/Red Caboose general service drop-bottom gondola. I weathered the car a bit and painted the wheel faces and trucks.

The wood cribbing, supports and spacers were based on prototype photos.

The steel bands were the narrowest chart tape I could find. They do not scale-out to a prototypical two inches and are closer to five inches wide. But they do provide a good visual effect.

This was a very easy project any modeler with a little experience and a few tools could accomplish.

Bob Chaparro

Scenery Material: Chinchilla Dust

I discovered this versatile scenery material while watching a video by Marklinofsweden on making Magic Scenery Dust. The video mentioned Chinchilla Dust as one alternative to making the Magic Scenery Dust seen in the video.

Here is a link to the video:

https://www.youtube.com/watch?v=VZgqDcNRNns

So what is Chinchilla Dust? It's volcanic pumice ground to a fine, non-magnetic gray powder that can be used for dirt roads and paths. It also could be used as ballast in scales smaller than HO.

I bought a twenty-seven ounce container at Wal-Mart for less than six dollars. Identical-looking (I checked) Chinchilla Dust also is available at PetSmart and Petco at a slightly higher cost per ounce.

I was hoping I could use it as a substitute for Monster Model Works "Dirty Dirt" as this fine scenery product no longer is available.

As it turns out, the Chinchilla Dust is finer and more gray than the Dirty Dirt.

But it still can be used the same way Dirty Dirt was used. And like Dirty Dirt, it does not darken when fixed in place with diluted glue or Woodland Scenics Scenic Cement.

I like the wide array of colors for various earth tones offered by Bragdon's and Doc O'Brien's weathering powders but these are much too expensive to use in large quantities to simulate dirt. But mixing these powders with the Chinchilla Dust at one-to-three ratio produces the same powder shades to use as dirt at a fraction of the cost. I found these mixtures can be applied just like the Dirty Dirt: Sprinkle on, dampen with wet water and apply Scenic Cement.

I assume powdered artist's chalk could be used in much the same manner.