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Peter's Model Railroading | The Layout | Stops | The Hazel Mine Complex | Hazel Mine Tipple
Tipple Design

 

The tipple building will be positioned on a very thin sheet of styrene, represented by this yellow surface. The purpose is to give me a nice, smooth, flat surface upon which to layout the grid for the structure's foundation blocks. All of this is very critical to get right, because there is very little clearance between the building and the rolling stock running through it. I am trying to build an accurate model of the actual building, so being precise in the planning and execution is important to me.

Based on the design diagram of the actual tipple, I concluded that the vertical columns of the building sat on about 3-foot square foundation blocks. Needless to say, the real-world foundation blocks and the columns went deep into the ground, but we don't have to model that. Through experience and testing, I learned that if I make the foundation blocks stick up above the track, some S-scale equipment will hit those blocks. The prototype drawings show the foundation blocks come up to just about the bottom of the axles on the freight cars, but that is too tall for me. So, you see the 44 foundation blocks drawn in this diagram only sticking up 14 scale inches from the styrene foundation, because that is about how tall the flextrack is that I'll be using.

The tipple building itself sits on a collection of columns, built somewhat like a trestle bridge. So, this diagram shows the 44 columns that hold up the building itself. Because of the way I built the building, the outer walls are a scale 5'4" lower than the central floor in the building, which is why the center two columns for the inner rows are taller than the outside columns. The outside columns are 33 feet tall. The building is 30'4" wide, so the four columns for each row are spaced 9' apart. The columns in the prototype were made out of two 10"- wide C-channels welded together. I am building them in the same manner, except using styrene and styrene glue. When two styrene C-channels are glued together, back-to-back, they measure a scale 8" deep.

The order of construction of the trestle will be such that I'll be building these four sub-assemblies first. So, the horizontal braces between the columns are connected next. Only the last four "bays" have horizontal braces near the ground; the rest are open for rail traffic and local-deliveries traffic.

Let's go ahead and bring in the five yard tracks that will be modeled on this module, so that you get a better idea of how things fit. When the building was original built in 1900, it only covered the first four tracks (as viewed from the right in this diagram). The fifth track was there, but it wasn't covered. A few years later, they extended the building to cover the fifth track, and also have two extra "bays". These were likely used for filling local coal dealers' trucks, as the mine supported local retailers.

The next logical step, of course, is to include the horizontal braces that go in between the sub-assemblies.

The main building sits on top of this trestle structure. The design excludes several details, such as the exhaust stacks, the windows, the X-bracing between the various columns, and the zig-zag braces put across the ends of the C-channels everywhere. If time permits, and it is easy enough to do, I may add some of these later on, but for now, this should give you a good idea of the Hazel Mine coal tipple building.