Car Forwarding on the 4th Subdivision -- Part Two: Car Flow

While recently running trains on the 4th Subdivision, I realized that I could be more purposeful in adding rolling stock to the Greenrock Turn beyond what I was setting out for Willow Springs. Since I have drafted plans for Nooksack, adding cars for that, as yet unbuilt, extension and adding additional traffic to the N. P. fiddle interchange will necessitate implementing (and perhaps tightening up) my process of "developing and organizing" car flow. In this post, I will expand on an earlier overview of my car forwarding process.

The first step is to research real and plausible industries. While planning Nooksack, I did a fair amount of internet research with the results described in an earlier post. Sadly, the industrial film about canning, linked in that post, has been removed from YouTube. More recently, I found additional information about potential traffic through the N. P. interchange. Kendall Quarry, near Sumas, Washington, shipped limestone to the Olympic Portland Cement Company in Bellingham on a local rail line. In my reality they will ship on the N. P. and the 4th Subdivision. In looking at a railroad atlas, I found that Yakima, Washington was served by the N. P. exclusively. HistoryLink.org has an essay on Yakima including apple crate labels from the 1940s. Apparently the "real" American Fruit Growers of Yakima liked the quality and price of my fictional Beise Box Company's fruit crates.


After research, the next step I take is to develop an on-line industry list. David Popp of Model Railroader created a blank example available for download and has written about using this form to assess demand. It is an easy form to recreate using the Word table tools. By using it to think about and record ideas, one can answer a number of car flow considerations:

• What materials will be shipped in and out of each industry?
• How many cars? What kind of cars will be needed?
• How often or how heavily will each industry be shipped?

As seen in my example, after filling out the chart, one can total the rolling stock to the right for the week and then, by dividing by the number of days of operation per week, an average number of cars a day. On the left, I found it helpful to write down a rough estimate for daily frequency of traffic for each industry.  As one creates these industry lists for the towns of their railroad, the lists can help determine if the railroad's capacity, in terms of staging and passing track length or number of trains, match the demand. 

In working out my original operations plan for Willow Springs, I wanted a way to move from weekly demand to a daily traffic flow that was fairly consistent from day to day. I ended up sketching out a car flow matrix with industries listed on a column to the left and days of the week listed across the top. Despite one glitch, to be discussed below, I feel this technique was successful enough to draft a blank form in Word to continue the same process for Nooksack. In my original matrix, I just included color-coded squares for the day the inbound or outbound car would be moved. I am still in the process of figuring out the scheduling or delivery of empty cars. My original system, ignoring empty cars, "worked" perhaps because I had a mix of inbound and outbound each day, so the travel of empty cars, from staging to "outbound" beforehand and from "inbound" to staging later, evened out. I jump started operations by pre-placing cars in outbound positions for the first day. 

Just a day or so ago, I tried going back and sketching in empty boxes for the empty cars to be delivered, but I don't know if that is necessary or desirable. 

Perhaps in charting out the potential flow for the additional rolling stock, I will use a two-toned bar for inbound and outbound to include the empty car travel. At the cannery in Nooksack, the same boxcars that deliver the can blanks will take away cases of finished canned goods, perhaps moving to a different door, but certainly not returning to staging during that time adding an additional variation. Having a blank form, with the industry names typed in, will give me the flexibility to try out some different ways of visually charting the car flow at Nooksack.

The next step in implementing adding rolling stock is to make sure that I have appropriate cars; that if they are kits, I have built them; and in either case, that the cars all hit my rolling stock standards. The next step in planning for car forwarding with new rolling stock is to start the car card and waybill process. Both of these steps are just now barely under way and therefore potential topics for future posts.