MQR Minimum Viable Design – Part 1

There is a concept in the software development world called the “minimum viable product“. From its Wikipedia entry, a Minimum Viable Product (MVP) is “one with just enough features to satisfy early customers, and to provide feedback for future product development.”[1][2]

I thought I would extend the concept to model railroad layout design to determine what would be the simplest design that met my goals for the MQR. A Minimum Viable Design is largely concerned about how trackage is connected to each other; concepts like the the geometry and length of the mainline, the minimum radius of curves, easements, siding length, etc will not be finalized until the final layout design.

For my former garden railway (pictured above), I could argue that the minimum viable design was in fact a circle of track. At that time, I really wanted no more than a loop of track to run my one train. The layout had two switches on it but I hardly used them at all.

Givens for the MQR

  • The design must support continuous as well as point-to-point operation, representing both ends of the line (Coed-y-Parc and Port Penrhyn)
  • Steaming-up of engines must be done off of the mainline track.
  • For the point-to-point option, it must be possible to prepare the train for its return trip without having to physically pick up any rolling stock or locomotives. This requires a runaround track at every end of the line. Turning of locomotives either by a turntable or wye is not required; the prototype Penrhyn Quarry Railway did not turn their locomotives.

Minimum Viable Design for Single Train Operation

It was reviewing Rob Bennett’s Weston Railway design that gave me the idea of the Minimum Viable Design concept: I liked the way Rob put the two “ends” of his railway beside and parallel to each other (lower right corner) but was concerned about the number of switches it took to implement.

Rob Bennett’s Weston Railway


Things clicked when I doodled out a design where the runaround trackage was shared by both ends of the line. To make this work, I felt it would be necessary to create some sort of visual separation between the two ends of the line.  The prototype Penrhyn Quarry Railway helped out here with the long slate wall on the south side of Coed-y-Parc.  Such a wall would not look out of place in Port Penrhyn either. This insight led to the MQR MVD #1a:

Marchlyn Quarry Railway Minimum Viable Design #1a

This design requires just 5 switches to meet the givens listed above for single train operation; the trade-offs are that: 1) for the runaround move, a locomotive must make use of the track at the other end of the line; 2) physically the two ends of the line must lie together and some means of scenically separating them must be devised. On the advantage side, this arrangement creates a working wye so that locomotive direction could be reversed if desired.

Typical operation would go like this:

  1. A train can be steamed up on either side but let’s assume the train is built up and steamed up on track B.
  2. It proceeds on track C towards the mainline.
  3. Entering the mainline on track D, it can extend its run using track E.
  4. To complete its run, the train enters track F and stops on track G. The locomotive is uncoupled from the rolling stock.
  5. The locomotive moves to track A, then backs up through tracks B and H until it reaches track F.
  6. The locomotive then pulls forward and recouples to the rolling stock on track G, ready to return.

Adding one switch removes the need for sharing the runaround trackage between the two ends and allows Coed-y-Parc and Port Penrhyn to be physically separated. This represents the MQR MVD #1b design:

Marchlyn Quarry Railway Minimum Viable Design #1b

This fundamentally is Rob Bennett’s Weston Railway design stripped back to its basics. Typical operation would go like this:

  1. The train is built up and steamed up on track B.
  2. It proceeds on track C towards the mainline.
  3. Entering the mainline on track D, it can extend its run using track E.
  4. To complete its run, the train enters track F and stops on track G. The locomotive is uncoupled from the rolling stock.
  5. The locomotive moves to track I, then backs up through track J until it reaches track F.
  6. The locomotive then pulls forward and recouples to the rolling stock on track G, ready to return.

Here I think the addition of one switch would substantially improve the overall operation of the layout, despite losing the wye.  In addition, it will make it much easier to scenic as Coed-y-Parc and Port Penrhyn no longer need to be co-located. In the next post, I will review the design in the context of operating two trains.

Inspirational 7/8″ Scale Railways

My previous garden railway (pictured above) provided me a lot of enjoyment over its four-year life. It was simple in design, quick to construct, easy to maintain and quick to dismantle when we finally moved. It was a great first outdoor layout for me but as I look to design and build the MQR, I am planning on setting my sights higher.

I’ve been a member of the 7/8″ scale forum, The SE Lounge, since 2007. Over the years, members have documented the creation and development of their layouts.  Here are three that have captured my imagination and will provide inspiration for the MQR design.

Rich Chiodo’s Isle of Shoals Tramway

If you are not familiar with Rich’s layout, I strongly encourage to go through all 23 pages of the post linked above. The IST is a wonderfully executed garden railway that fully captures British narrow gauge.

Things I like about the IST:

  1. The brick tub supporting and surrounding the IST is just gorgeous; it creates a nice edge which photographs well. However, Rich mentioned that it took a long time to construct. 30″ feels about the right amount of elevation to design for.
  2. Rich’s design allows access to all parts of the layout.
  3. Low track-to-scenery ratio.
  4. Very simple track work: wide curves, little straight track, 5 switches in total.

Things I’d do differently:

  1. I would like to have the option to run both point-to-point and continuously.
  2. I am on the fence when it comes to the “pit”. It is a sunken area in the middle of the layout where people can sit and enjoy the layout from a different angle.

Chris Bird’s Summerlands Light Railway

Chris has documented his layout extensively on YouTube.

Things I like about the SLR:

  1. Once again, a very simple track work: wide curves, little straight track, 6 switches in total.
  2. Many small scenes that photograph or video well and make the layout seem much bigger than it is.
  3. Because Chris has included a reserve loop, he can run the SLR in an out-and-back configuration.
  4. The layout is elevated along the main operating side; looking at photographs, I would estimate the elevation difference to be about 15-18″.

Things I’d do differently:

  1. I’m unlikely to have tunnels on the MQR.
  2. No passing loop on the mainline.

Rob Bennett’s Weston Railway

Rob Bennett is another well-known 7/8″ scale modeler from the UK. As I understand it, his Weston Railway was originally at ground level but was elevated in the late 2000’s. I mostly seen Rob’s layout through the various YouTube videos he has made.

Things I like about the Weston:

  1. The two sets of spurs running off to the lower right give Rob the option of running point-to-point. They also serve as steam-up bays.

Things I’d do differently:

  1. The Weston is quite a bit more complicated in track design compared to the IST and SLR: I count 16 switches in Rob’s diagram. I expect the MQR design to come in around 10 switches maximum.

Design Flavour for the MQR

Now that we are back in Canada full-time and know where we will be living long-term, I’ve initiated the planning process for the 7/8″ scale Marchlyn Quarry Railway. To start, I’ve pulled together a number of photos of the prototype Penrhyn Quarry Railway for reference and flavour.


This was the south end of the Penrhyn Quarry Railway. Here the PQR connected with the slate quarry.  Coed-y-Parc was also the location of the main slate dressing mills, the sheds for the steam engines as well as a small yard for marshalling the trains to Port Penrhyn. Coed-y-Parc featured a beautiful road bridge splitting the Coed-y-Parc yards in two. It also featured an impressive slate wall on the south side of its property that ran the length of the yard.

Slate Sorting Sidings, Coed-y-Parc, 1962
Felin Fawr, Coed-y-Parc, 1962
Felin Fawr, Coed-y-Parc, 1962
Coed-y-Parc Bridge and Wall, unknown date

Hendurnpike Crossing

Hendurnpike featured a picturesque road crossing. The original crossing guard’s shed was still standing in 2013!

Hendurnpike Crossing 1962
Hendurnpike Crossing, 23rd February 2013


Tregrath was the location of the main passing loop about halfway between Coed-y-Parc and Port Penrhyn.

Tregarth Passing Loop, 1963

Port Penrhyn

Port Penrhyn was the north end of the PQR and where the finished slate was transferred to boats and ships for export. Port Penrhyn was also served by the standard gauge British Railway, making for some interesting trackwork.

Approaching Port Penrhyn, 1961; Standard Gauge British Railway to the left
Port Penrhyn Decks, 1961
Port Penrhyn, 1964

How To: Google Maps and 3rdPlanIt

The availability of digital satellite photos through services like Google Maps and Bing have yielded a wealth of information for the modern age modeler. One of the challenges though is how to leverage satellite photos inside powerful layout design tools like 3rdPlanIt. I’ve been working through this over the past few days and feel I’ve arrived at a good efficient process.

Let’s see how this works in practice. I’ve selected the Ingredion siding (formerly CASCO) in Port Colborne, Ontario on the Trillium Railway as an example. The Google Map is available here.

The first step is to get a screen capture from Google Maps of the area you want to model. It almost always pays to make the screen capture as big as possible. I use the Snipping Tool that comes with Windows with the Window Snip option to get the whole browser window. Go to Google Maps in satellite mode and zoom into the area you want to capture. I try to get down to a consistent zoom level which makes the next steps a little easier. The most important thing to remember is to get the little scale that Google puts on every map into the screen capture (using the Window Snip option should ensure this happens). On the screen capture below, the scale shows 20 meters since I did the screen capture in Europe:

Step 1: Get Screen Capture from Google Click to Enlarge
Step 1: Get a Screen Capture from Google
Click to Enlarge

Using the Save option in the Windows Snipping Tool, save the screen capture as a jpg and note the size of the jpg; on my system, the size of my monitor gives 1920 x 1168 pixel screen captures.

Next, open 3rdPlanIt and start with a fresh file working in feet and inches. The 20’x20′ default room is a good one to start with. It is also good practice to add a new layer to hold the aerial photograph:

Step 2: Set up an Aerial Photo Layer Click to Enlarge
Step 2: Set up an Aerial Photo Layer
Click to Enlarge

The next step is to convert the dimensions in the 3rdPlanIt file to model scale units. There is a checkbox on the File/Settings/Units that you must click. This converts the dimensions in the 3rdPlanIt file to real-world units. For an HO scale drawing, every dimension gets multiplied by 87.

Step 3 Convert to Model Scale Click to Enlarge
Step 3 Convert to Model Scale
Click to Enlarge

Now with the Aerial Photo layer active, select the “Place Image” tool. Starting at the (0,0) corner (the lower left), click and drag your cursor until the size of the photo is about 19200″ by 11680″. This is the proportion of the jpg file multiplied by 10 and should just about fill the 20′ dimension. It is critical to keep the proportion of the jpg when drawing the object; once the image is placed in the right proportion, we can drag the upper right corner to bring the image to the final dimensions. Working in HO scale here and with the level of zoom I typically work, I find that I need to make the jpg image about 22 feet wide:

Step 4 Resize Photo Click to Enlarge
Step 4 Resize Photo
Click to Enlarge

Once I’m at this point, I switch the units to meters to align with the Google Map scale and switch the layer to the Main Layer. Now, zoom into the Google scale section and the bottom right. Select the Draw Track and draw a piece of track from one end of the scale to the either. Now check the length of this track segment in the track detail box in the top right. If the two are close (say 21 meters compared to Google Maps’ 20 meter scale), then you are done. If they are significantly different, select the placed image again and grabbing the same upper right corner, increase or decrease the size of the image accordingly and redraw the check track segment again:

Step 5 Check Scale Click to Enlarge
Step 5 Check Scale
Click to Enlarge

Now you can return to the Main Layer and start drawing track right over the Google map. I usually start by putting turnouts down first. Next to be drawn are the end of the various spurs. I then use the SoftTrack connect tool to tie them together. If the Google Map satellite photo has railcars on the spurs, I’ll often add a couple of them from the Rolling Stock library to confirm I’ve got the scale right:

6 Draw on the Aerial Photo Click to Enlarge
Step 6 Draw on the Aerial Photo
Click to Enlarge

From here, you can just group the trackage in the Main Layer together, copy it and paste it into your layout design file as a Layout Design Element.

What’s nice about this approach is that it gives you a good feel of the track arrangements on the prototype and how much space would be required to model things faithfully. For the Ingredion spur, the prototype would take about 12 feet to model faithfully, a luxury many of us would not have. However, from here, we can build up our strategies to selectively compress scenes like this one for modeling.

Video: Port Colborne Harbour Railway

This is another interesting video of the Trillium Railway operations circa 2012. The back story is that CP was on strike at the time, preventing Trillium from using its normal interchange at Feeder. Instead interchange was done with the CN at Merritton. The video shows that all three Trillium locomotives were called into action.

Trillium Railway Detour Interchange, Merritton, May 26, 2012

The video does show the differences in traffic between the north and south parts of the railway. The south part is dominated by tank cars and covered hoppers, while north of Merritton, boxcars and gondolas are more prevalent.

Photo Set: On TraXS 2015

I returned once again to the Dutch Railway Museum for the 2015 edition of On TraXS. This year 27 exhibition style layouts were set up throughout the museum. While the number of layouts was down slightly from last year, the number of vendors in attendance was up significantly.

Once again, there were some very well-done layouts on display. I especially liked:

  1. Pit Karges, First Snow on the high line, HOn3
  2. Collectief Chemin de Fer Forestier, Mocanita, Oe (it’s based on a real railway)
  3. Halleluja Players, Orange River & Pacific, Fn3
  4. Thomas Schmid, Île VaOù, Oe
  5. Arcamodellismo Torino, Vallescura, HO
  6. S&G hardrock mining, Leo Bettonviel, HOn3

It was interesting that HOn3 was so popular this year; in 2014, On30 was the preferred narrow gauge scale. And while it is not a traditional model railway, the execution of Peter Dillen’s IJsselstein module, with its use of perspective, was stunning to see in person:

IJsselstein by Peter Dillen
IJsselstein by Peter Dillen

As always, I’ve made a photo set available on Flickr.

Riding the Little Trains of Wales

Robin and I have just returned from two weeks in Wales where we hiked, walked around old castles and manor houses and rode four of the Great Little Trains of Wales. The four railways we rode were:

  1. the Llanberis Lake Railway
  2. the Welsh Highland Railway
  3. the Ffestiniog Railway
  4. the Talyllyn Railway

On the Llanberis Lake Railway, we rode behind “Elidir“. We used the Welsh Highland Railway to complete a hike we did from Rhyd Ddu to Beddgelert. We photographed both Garrett engines used on the WHR, numbers 138 and 143, earlier in the day when they crossed near Rhyd Ddu but rode behind no 138 back to Rhyd Ddu. On the Ffestiniog, we rode the “David Lloyd George” down from Blaneau Ffestiniog to Porthmadog and the “Earl of Merioneth” back up. Finally, on the Talyllyn, we rode behind the “Tom Rolt“.

Each trip had its own highlights, but having the opportunity to see these classic steam engines running through the Wales countryside was reward enough.

I have additional pictures from the Llanberis Lake, Welsh Highland and Talyllyn Railways on Flickr.

The Penrhyn Quarry Railway

The Penrhyn Quarry Railway was possibly the first two foot gauge railway in the world, the quarry it served the largest slate quarry in the world, the slab mill and inclines the oldest in Wales. All this makes this iconic railway of national, if not global, importance. After 167 years of service, the Penrhyn Quarry Railway was closed in June 1962, most of the locomotives finding new homes throughout the world.

Several good websites document the history and current status of the PQR. The Penrhyn Quarry Railway Society supports the rebuilding of the railway and actively acquires historical artifacts and photographs of the railway and quarry. The Penrhyn Quarry Railway provides support for the Penrhyn Railway Project at Felin Fawr, Bethesda. Support includes funding small projects and promoting the railway and its heritage.

To give you a feel about the PQR near the last days of its operations, the following Youtube video shows some vintage footage from the 1950’s:

Sixty years later, here are some of the preserved engines and rolling stock of the PQR running on the Llanberis Lake Railway.