X marks the spot

Hot on the heals of my blog post describing the town of Rosa Park, I thought I should explain how the diamond crossing is going to work since it is a rather important operational feature on the model railroad.

As stated previously, the diamond is necessary to bring the BN/BNSF track from an outside curve on the visible part of the layout into staging which is on the inside of the layout. The BN/BNSF tracks essentially loop around the lower deck but travel only through Marshall on the layout itself. Although the focus of the layout is the Dakota, Minnesota and Eastern (DME), I wanted an interchange with the BN/BNSF and I also wanted to just run a train in a continuous loop at times while working in the garage. But I also wanted the DME line towards the rear so I could place industries along the backscene and to enable it to leave Marshall on an incline (hidden) behind the garage doors to get to the (to be constructed) upper deck. After all, the upper deck is essentially the DME line from Marshall to Evan that I am actually modelling.

Here is an earlier generic plan of the layout, albeit some changes have since been made and I will mention one of those changes now. You can see the position of the town of Rosa Park and how the DME and BN/BNSF lines cross as they approach the peninsula. You can also see the BN/BNSF staging area behind Rosa Park and how it loops around behind Ivanhoe to cross over the doorway from where it can make a continuous loop. In this plan DME staging is to the left of the doorway but this has now changed to BN/BNSF stub-ended staging and the new DME staging is along the back of the garage doors. The new DME staging area can hold four staging tracks and the incline from Marshall to the upper deck, even if the diagram suggests insufficient space!

Positioning planPhoto 1 shows the diamond crossing and the BN/BNSF track moving from the outside to the inside of the baseboard where it joins the staging yard on the blue mat. This is an older photo and doesn’t show the final track positions in staging. The position of the water tower is still to be determined but it will have a critical role to play as I will explain shortly.

Photo 1:

Rosa_Park_staging_diamond_1The diamond crossing is not considered part of the railroad. What do I mean by that?

The crossing is a necessary part of the model railroad in order to move BN/BNSF trains from one position on the layout (the visible part) to another part of the layout where trains are stored in staging, or can complete a continuous run. As such, the BN/BNSF trains are considered to be moving through Marshall or they are somewhere else. There are two explanations for this: the first is that we consider offstage storage of trains to be representative of other parts of the railroad (e.g. an extension of the Marshall subdivision and other connecting parts throughout the United States) when we think of the prototype. However, we also need to consider that we are also operating a model railroad and we need to work out how best to channel trains from one place to another for model railroad storage purposes. So long as the model railroad storage purpose is not visible to us, we can maintain the illusion that our trains are moving through Marshall and going to another place – Wilmar, the Twin Cities, Sioux City, Kansas City, Spokane, the Pacific and Atlantic coasts, etc. I therefore have no problem moving my trains offstage in whatever manner best suits to maximise the operation of the trains on the visible part of the layout. This is not revolutionary by any means: some layouts have offstage storage where trains are built up by pulling freight cars and locos off shelves or from drawers.

In Photo 2 we see a mock up of the backscene boards used to separate the visible layout at Rosa Park and the hidden staging. Note the short board hiding the diamond from Larraway Lumber. It does look a tad messy but I am hopeful that with the right buildings and backscene the gap won’t be as obvious. But yes, one will indeed see a “mousehole” when looking from either side of this part of the layout (i.e. trains entering from the curve around the peninsula or when DME trains drive through Rosa Park to Marshall). For now, I will call it a transition zone and leave it that! The transition zone does not exist on the railroad, much the same as a helix does not exist on a real railroad. I will need to find a name for it though because the dispatcher must tell BN/BNSF crews when they can cross the diamond, while crews need to tell the dispatcher they are positioned short of the diamond and ready to come out onto the layout. And this is especially important for safe working.

Photo 2:

Diamond_crossing_2 The envisaged safe working procedure is actually pretty simple. Please note that I am about to explain the safe working procedure for the model railroad. DME trains do NOT have to seek permission from the dispatcher to travel through the transition zone between Rosa Park and Marshall. The default on the DME is that the transition zone does not exist. However, all BN/BNSF trains MUST stop on approach to the diamond from staging (i.e. from the right). The dispatcher can only allow a BN/BNSF train onto the layout by crossing the diamond when no DME trains are coming through. Once a BN/BNSF crew have the OK to proceed, their train crosses the diamond and enters the visible part of the layout on the outside curve of the peninsula which takes the train to Marshall. Once the train enters the visible part of the layout, the train is now “on the prototype” and will operate accordingly.

In Photo 3 we see a coal train crossing the diamond only after the dispatcher gave permission for this train to be at this point on the layout. This is naturally the case for the train coming from both directions. For trains coming from the east (the left) that will leave Marshall to go around the outer curve on the peninsula, and enter staging by crossing the diamond (from the left), the crew will get permission from the dispatcher when the train first arrives in Marshall. These trains actually originate from one of the four stub-ended sidings behind Rosa Park and continue behind Ivanhoe to cross the doorway and enter the BN/BNSF main just before the MSC/ADM industrial complex. Staging and operation around the doorway is actually handled by a yardmaster rather than the dispatcher but both yardmaster and dispatcher are in communication with each other.

Photo 3:

Diamond_crossing_1

Note that ALL DME trains take precedence. If a DME train will be in the way the dispatcher will hold the BN/BNSF train in staging or at Marshall until the passage is clear. Holding a BN/BNSF train in Marshall might be for any number of prototypical reasons, but holding for “the diamond crossing to be clear” won’t be one of them.

In photo 4 we see the same coal train crossing the diamond. Let’s pretend it is actually moving from right to left as though it has come onto the layout from staging. But how did the crew and the dispatcher know where the train was prior to getting permission to move onto the layout? The diamond in this transition zone will be hidden, as are the storage sidings themselves (remember that the upper deck will be over the top of the storage sidings eventually).

There are two options. The first is the use of a small wireless camera and screen but I am still to be convinced that this is the best approach. The second option is a little more creative and potentially offers the right type of information using a sensor and a LED.

And this is where the water tower comes into the picture. I envisage having a small light on the top of the water tower (I think Model Power or Korber might have even have sold water towers with blinking lights on top) which is activated by a sensor (an IRDOT most likely) when the BN/BNSF train is about 6-8 inches from the diamond. When the light is activated by the sensor the train must stop until given the OK to proceed by the dispatcher to cross the diamond and enter the layout (and thus now on the railroad). I need to give this spot a name (most likely a town). The crew can alert the dispatcher by saying that the train is at Split Rock (for example) and the dispatcher can say to hold at Split Rock or to proceed from Split Rock.

Photo 4:

Diamond_crossing_3The water tower now becomes an important signal for crews to know where their train is and when to stop their train prior to crossing the diamond and entering the visible part of the layout.

This is just speculation at this stage of layout construction. However, considering different operational options and making the distinction between prototype and model railroad is already making a difference to how I think about potential track changes and operation strategy. The proof of the pudding is yet to come. But at least we can start imagining the taste and what it might look like while it is still being cooked up.

Advertisements

Rosa Park on the DME

The town of Rosa Park is located between Ivanhoe and Marshall in southwest Minnesota. Rosa Park is a major beneficiary of the Dakota, Minnesota and Eastern (DME) rail line from Brookings (SD) to Marshall (MN) and beyond. The DME line from Brookings to Evan (MN) (rejoining the DME main line just west of Sleepy Eye) is called the Evan subdivision, or more colloquially known as the DME Deviation. The DME has been a key driver of economic development at Rosa Park and demonstrates how important rail can be to a town’s economic base.  Being located close to Marshall and the BN/BNSF interchange also helps. Rosa Park has a number of significant industries that rely on the DME and support a local population of almost 3000 people. Workers also come from neighbouring Ivanhoe and Marshall.

The schematic for Rosa Park and the BN/BNSF hidden staging gives readers a good idea of the track configuration and industries served by the DME line. The red line shows the separation between the visible part of the layout (Rosa Park) and the hidden staging tracks for the BN/BNSF behind it.

Rosa_Park_and_staging_amendedPhoto 1 shows Rosa Park and the BN/BNSF staging area behind it. The photo looks down on Rosa Park from the east (left hand side). The yard length is about 5m (approx 15 feet). The slightly obscured blue DME loco behind the water tower is on the DME main line.

Photo 1:

Rosa_Park_updatedIn my original plan for Rosa Park, the grain elevator was going to be situated at the front edge of the baseboard with only a single spur. The actual elevator structure and grain silos were to be “imagined” in the aisle space. Where the grain elevator is now located was to have been a Central Soya complex. I quite like the Central Soya covered hoppers and tank cars and I have several of them. However, having two large soy processing complexes (the other being the Minnesota Soy Processing Co-op at Marshall) was too much. Interestingly, Central Soya started in Indiana in 1934 and expanded into other Midwestern states. Central Soya was purchased in 2002 by Bunge Limited after having been part of the Cereol Group for a number of years.

When I decided to replace Central Soya with the grain business at the back of Rosa Park, I did have a concern that the modelled grain elevator would protrude slightly into the edge of the upper deck.  I will work my around that issue when the upper deck gets constructed, but I have a couple of suitable options to overcome that. You can see in Photo 2 below that the grain silos are slightly higher than the unpainted and temporary backboard. And yes, the water tower is in a different position in this photo!

Photo 2:

Rosa_Park_staging_2The current yard layout and industries at Rosa Park are now settled and the trackwork has been altered accordingly. The main industry is a large grain elevator and associated fertiliser distribution business – Saatkamp Grain and Feed.  Because of a limited track lead, a pair of turnouts in the yard allows grain trains to be broken up and fed through the loading facility in two lots. The grain elevator has its own switcher and I am still to decide whether to use a SW1500 or NW2 for that role as I have both as options.

Another change to the original plan was the addition of an extra 11 cm to the front of the baseboard at Rosa Park (this is visible in the photos as a lighter shade of plywood). This enabled an additional spur plus room for industry structures along the front of the layout. Being at the front, I wanted industries that were not very tall so they didn’t interfere with reaching into the yard during switching operations. I fictionalised that the former iconic Minnesota supermarket chain, Red Owl (which was taken over in 1988 by Super Valu), re-established itself as an independent entity in the early 1990s and had a major distribution warehouse at Rosa Park. Such an industry allows for a variety of incoming freight cars. The other industry at the front of the layout is Sealed Air, a company that makes packaging material like bubble-wrap.

Photo 3 shows Rosa Park with all the industry sidings. The staging tracks are on the blue mat. Originally, I had seven tracks in staging but the gap between tracks was too tight so I lifted the track and put down the six tracks you see in the photo.They look a bit wobbly and that’s because they have not been fixed into place yet. These tracks will be straightened and Tortoise motors installed onto the turnouts. The turnouts on Rosa Park will be thrown using manual ground throws.

Photo 3:

Rosa_Park_and_BN_stagingFrom the opposite angle, Photo 4 shows the configuration of the DME tracks. From left to right: Red Owl and Sealed Air industry tracks; siding; passing loop, DME main line; and the three grain elevator tracks for Saatkamp Grain and Feed.

Photo 4:

Rosa_Park_midPhoto 5 shows the west (right) end of the Rosa Park yard and the curved track of the DME main that rounds the bend into Ivanhoe. The two forked tracks are the ends of the grain spurs. To the right of the DME main line is a short curved lead track. Originally this was to be a spur for a propane gas facility and I am still considering this option. The two tracks leaving the blue mat are the main and loop siding on the BN/BNSF staging that will curve around behind Ivanhoe and remain hidden until it crosses over the doorway (see previous blog post).

Photo 5:

Rosa_Park_west_endPhoto 6 shows the east (left) end of Rosa Park. The spur on the far left with the red box car is Larraway Lumber and Building Products. Midway along on the left are two sidings for Sealed Air;  the one with the covered hopper is for discharging plastic pellets and the spur off to the left with the brown box car is for incoming and outgoing products. The BNSF coal train is on the run through line in staging.

Photo 6:

Rosa_Park_east_endAt this eastern end of Rosa Park, I have made some more room at Larraway Lumber to allow for a larger complex than originally planned (Photo 7). I was keen to ensure that the unloading of wrapped lumber from centre-beam freight cars could be done from both sides as on the prototype. Accessing both sides of the centre-beam freight car is necessary to prevent the car from falling over if only unloaded from one side! To save space, one side of the unloading area is “imagined” in the aisle. Larraway is a real business in Minnesota, although not rail served, and is in keeping with my desire to include things I saw on my previous trips to DME territory.

Photo 7 also shows how the BNSF line (outer curve) crosses the DME main (inner curve) to enter staging on the right from the actual visible part of the layout. The end of the visible portion of the layout is where the cross-member and vertical post are. Larraway Lumber will help conceal the diamond which is not part of the visible layout.

Photo 7:

Larraway_Lumber_positionThe diamond is necessary to bring the BN/BNSF Marshall subdivision line into staging as on the layout (lower deck) it is on the aisle side of the baseboard. The hidden staging behind Rosa Park has six tracks. One of the tracks is a run-through track and a second is a loop siding. There are four stub ended sidings. The backscene behind Rosa Park will be removable to allow access to these hidden staging tracks. I plan to experiment with track detectors and a couple of small cameras linked to two screens at either end. The hidden staging will sit below the upper deck and will be enclosed, other than for the ends of the stub-ended spurs near the dispatcher’s well.  I will describe how the tracks from hidden staging behind Rosa Park connect to the rest of the layout in another blog post.

One feature I have experimented with in this section of hidden staging is the use of a (blue) camping mat on the surface of the plywood instead of cork (Photo 8). I purchased the camping mat cheaply from a two-dollar shop (albeit paying slightly more than two dollars).  I am interested to find out whether it lowers train noise compared to cork.

Photo 8:

BN_BNSF_staging_matRosa Park is a key location on the layout with plenty of operational potential and industry activity. While the town is fictional, its economic base and characteristics are in keeping with the prototype. As an example of using the rail system for regional development, I consider Rosa Park to be a big success.