Passing Time at the Airport

We were early back at Sea-Tac and had a couple hours to pass before boarding, so I spent some time taking photos.

Night at South Lake Union

Nice view after great Neapolitan Pizza at Tutta Bella

In the air again

A quick trip to the Pacific North West.

As we start our descent into Sea-Tac, the sun and clouds frame our shadow with a circular rainbow.

I don't think I've flown the approach from the North into Sea-Tac yet. Great scenic loop over the Pudget Sound and past downtown Seattle. However, I don't think the locals are as excited about this flight route as me ...

Der Tunnel - Verbindungsbahn der S-Bahn Stuttgart

It's rare that railroad projects are documented in vast detail from the perspectives of civil engineering, economics, and social impact in a single book. "Der Tunnel" is one of the exceptions. It describes design and construction of the central element of the S-Bahn Stuttgart: The city tunnel between Hauptbahnhof (main station) and Schwabstrasse, and it's underground continuation to Vaihingen via Universität. In over 35 detail-loaded chapters the authors work through early plans and financing of the project, discuss in detail the various construction sites within the city core, including engineering challenges of constructing a tunnel in the middle of a bustling city with difficult geology. They keep the high level of detail as they discuss the concerns and engineering challenges building the Hasenbergtunnel towards Vahingen.

Along the way they touch on such diverse topics as re-routing of sewers, tram lines, and car traffic; digging next to, or under, historic building; construction impact litigation; project financing; operational aspects resulting from tight headways of S-Bahn trains; supply and material logistics; geology of Stuttgart's underground; triangulating underground with high accuracy and verifying construction to plan; etc. etc. etc.

Hamburg method vs. Berlin method of open tunnel construction - spot the difference!

In addition to the general civil engineering aspects of the project, what I found most interesting are the many descriptions of when things were built differently than originally planned, or when things went wrong unexpectedly and what to do about it. Above is an example of how a different tunnel construction method was chosen in Rotebühlstrasse near Feuersee to get a narrower construction site and gain just under two meters extra space between the construction site and buildings lining the street to facilitate surface traffic and building access.

The book has answers for civil engineering questions I asked myself when riding the train. E.g. the lower half of the Hasenbergtunnel is constructed as two single-track tunnels that merge to a single two-track tunnel in the upper half towards Universität. You can hear the difference as the tunnel transitions when riding the train between Schwabstrasse and Universität. The reason is due to geology. The lower half of the tunnel lies in keuper gypsum ("Gipskeuper") which can develop a lot of pressure on the tunnel bores due to swelling of the gypsum in combination with water. Constructing two smaller circular bores made it simpler and more cost-effective to provide for the necessary fortification of the tunnel against rock pressure in this stratum. In the upper part of the tunnel, the gypsum over time has been washed out from the keuper rock and thus it can't develop the same amount of rock pressure on the tunnel bore. Building a larger diameter two-track tunnel was more economical in this section.

While I was studying at Universität Stuttgart, I used the infrastructure described in this book daily, so I -- along with many others that lived and live in the Stuttgart area -- have developed a special relationship with the S-Bahn. We use it daily and take it for granted. This book is an interesting look behind the scenes of what goes into such major infrastructure projects, and also provides historical perspective on changes in planning and construction methods during the early 1970's and early 80's, a period of transition towards a computerized world. 

"Der Tunnel" (ISBN: 3-925565-01-9) is written in German, was published in 1985, and can occasionally be found secondhand on abebooks, booklooker, or other sources for antiquarian books.

ETE: Bay Area Module Group at Oakland Aviation Museum

601 004 traveling across the Danish country side.

Fast-forward 50 years: 442 206 crosses a bridge that could be located in the Black Forest.

Today I hung out with the ETE Bay Area Module Group at the Oakland Aviation Museum. I even brought some trains with me.

This was a great opportunity to run the BR 601 in Intercity service in its full length consist with 8 cars, which looked great running on the long main line loop the group has set up. 

I had a lot of fun running trains, chatting with friends, and enjoying the atmosphere. The museum was quite empty, which was a pity since there's lots to see besides model trains, especially if you're into planes.

I took a short video, too.

Roco 43012 - Preparing for an Outing

 [ 601 posts ]

I haven't worked on the BR 601 3-rail conversion project for almost 3 years now. I was stuck on a mechanical drive train problem, how to install lights, and how to power the sound decoder for the rear motor unit. In addition, the full train is too long for the Welztalbahn. So several intermediate cars stayed in the box, and a shortend train with the two power cars sat on a storage track in staging. 

Now I have an opportunity to run the train in its full-length glory on a larger layout in public, so I finished swapping all wheel sets for their respective AC counter parts and installed the hand rails at all doors. I'm not going to be able to finish installing the sound decoder in the second motor unit before Monday, nor lights or passengers. That will have to wait for another time. I hope that I can resolve the drive train problem today or tomorrow.

SVL: August Modern Ops Session

For the first time in months, I was able to participate in an ops session at Silicon Valley Lines in person again. This was a nice opportunity to catch up with other club members and enjoy the atmosphere of being in the layout room. I ran Bayshore Yard, which was a very relaxed assignment with plenty of opportunities to railfan trains run by remote operators.

1000 pieces in 10 days

In case you were wondering what I have been doing lately, here's part of the answer. Not only was there a lot of reading material on a recent transatlantic flight, but also this puzzle (Ravensburger No 16 726 5, "Danzig").

Didn't look too hard, so I started it on the living room table last week. The house fronts were fairly easy once I zeroed in on colors and window styles. Filling in the roofs and surroundings was an exercise in occasional frustration. However, with persistence and patience I eventually finished it. It was a slow-going slog for most of the time, except today. The last 100 pieces almost placed themselves.

Delivery from Germany

I have not been to Germany for a while, so various ebay orders have been piling up at my parent's place. This summer two of our children went to visit family, and they brought back a treasure trove of stuff. Lots of original paperwork from the 1970's, including schedule books, maps, and a Güterkursbuch from 1972. Various books and magazines about the Bundesbahn in the 70's, some original artifacts, and some history books about railroads in Württemberg. I also picked up a collection of original rules and regulations from the 1930's, 40's, and 50's.

Lots of stuff to go through. I'm planning to post some of the more interesting original paperwork here over time. 

Untergroeningen Station Building (2)

 [ Untergroeningen posts ]

[ part 1 ]

I've constructed the station building shown in part 1 in Tinkercad, which is a very easy to use online 3D CAD tool. I know it mostly as a tool for users that want to send the resulting model to a 3D printer. Tinkercad makes exact sizing of the model very easy. Measurements of elements are readily accessible, and changing values is trivial.

Developing a 3D model from photos and drawings is interesting. Especially the roof geometry remained a challenge, though at last I finally figured out what the geometry actually must have looked like, based on how the roof lines develop from the walls and what I can deduce from photos taken at eye level from the ground. 

I didn't want to 3D-print the station building, but rather wanted to build a paper model. Much more economical than springing for a 3D-printer and filament. There are many instructions and tools to unwrap 3D models. Dedicated payware like Pepakura (Windows only), Unwrap3D, plugins to Blender, or the native UV Editor built into Blender. I found that unwrapping the whole building became very cumbersome, so I exported only the roof structure as STL from Tinkercad, imported that to Blender, manually set seams using the UV Editor, and constructed a sensible unwrapped roof. Exporting the unwrapped roof from the 2D view in Blender leads to a very low-resolution PNG. I took a screenshoot instead, scaled it to the right dimensions in GIMP, and printed it. Not high-quality, but more than sufficient to cut the shapes. Since the walls are basic boxes I just measured and cut lengths of card stock in the right dimensions.

The photo above shows my first attempt of the paper building on the Untergroeningen module. While the walls look properly proportioned in the 3D model on screen, the paper model is a bit too plump, or fat, when comparing to prototype photos. The roof seems to be a bit too flat as well. The next version is going to have slightly higher walls, and a slightly steeper roof. Adding 3mm to each story and the roof should do the trick.

When comparing with a freight car on the tracks, the building sits too low as well. I need to raise the ground a few millimeters and have a proper building foundation.

Otherwise, I'm pleased with how this scene is developing.

Untergroeningen Outbuilding - Completed

 [ Untergroeningen posts ]

[ part 10 ]

The outbuilding is now completed. I added windows and added more weathering. This was a fun build and gave me confidence that I can tackle the larger challenge of scratchbuilding the main station building.

If you want to read the whole story of constructing this outbuilding, start here.

Untergroeningen Station Building

 [ Untergroeningen posts ]

With the outbuilding mostly completed, I'm starting to work on the station building of Untergroeningen. I have photos. I have an aerial photo. What I don't have are reliable measurements. I made drawings and a mockup from paper, but I felt that the building proportions were not quite right. A couple days ago, I started constructing the building in 3D from the drawings I made earlier. The idea is to replicate viewing angles I have as a photo and see what the 3D model would look like. This is not perfect, since lens distortion and other optical effects get in the way, but I'm hoping to get closer. Here's me first try. Not too shabby, but the proportions are indeed not quite right. I think I might have made the building a bit too deep, but it's hard to tell on the screen.

If only I could make a paper model from the STL 3D model ...

Untergroeningen Outbuilding (10)

 [ Untergroeningen posts ]

[ part 9 ]

We're coming close to the end of this build. The Outbuilding is basically done. It's missing only the windows and the foundation. The windows will come when I have decided whether to scratch-build, kitbash, or 3D-print them. The foundation will be part of the final installation in the Untergroeningen module, so will come at a later time.

Meanwhile, I have completed the garage doors, added the gable barge boards, a venting pipe, downspouts, and the concrete "Schamwand" in front of the restroom doors. That wall likely used to be made from wood way back when the restrooms were built, and replaced with a concrete wall as the old wooden wall was falling apart. I assume the building got a refresh in the early seventies. Hence, the relatively new roof and mostly spotless garage door, too. 

None of the prototype photos I have show the outbuilding in the early seventies, so I took some artistic license here.

[ finale ]

Untergroeningen Outbuilding (9)

 [ Untergroeningen posts ]

[ part 8 ]

It's time for the roof. I cut the roof from a Kibri sheet, air brushed with a mix of red, yellow, and brown and accentuated with a alcohol / india ink wash. The gutters are from an old Auhagen roof details set. I made the peeling green paint effect on the gutter with an Aquarell pencil. The gutters are a bit too long and will need a new end piece fitted later. 

I always have some trouble determining the proper length of roof pieces, and often cut the first piece a little bit too short. Getting this right on the first try is not really that hard, but I usually only notice it when I glue the piece to the building. So far I've always managed to mostly disguise my inability of cutting properly sized roofs.

Once the gable barge boards are fitted, you won't be able to tell that one roof sheet is a bit taller to make up for the shortness of the other one.

[ part 10 ]

Untergroeningen Outbuilding (8)

 [ Untergroeningen posts ]

[ part 7 ]

With the base color done, it was time for some detailing. I don't have the right colors to faithfully replicate the colors of the prototype, but I was after a believable brick structure that has some life in it. I experimented with various different approaches on a test piece -- visible behind the outbuilding in the photo below -- and then settled on a technique using Aquarell pencils. I first highlight individual bricks using various Aquarell pencil colors. Of course, the bricks are pretty small, so I usually hit more than one brick at once, and also don't color all the bricks. That's ok. I'm after variety here. For the color palette I chose various dark orange, red, and yellowish tones, as well as gray and black. 

Once the bricks are highlighted and the Aquarells are dry, I flood the mortar lines with an alcohol-based wash made from ModelMaster Flat Cement, plus a couple drops dishwashing liquid. I apply the wash with a fine brush and let the wash run into the mortar lines. Some color will get on top of the bricks and create more color variations. If it gets too much I can wick some of the wash into a damp towel, or direct the wash with the brush to another part of the model.

Once the mortar lines are to my liking and dry, I darken the timbers with a thin layer of Aquarell black and add some highlights with Aquarell gray to suggest aging wood.

[ part 9 ]