Fort Pitt Bridge Works
08/09/2017
The Fort Pitt Bridge Works was a large factory started in 1896 in Canonsburg, Pennsylvania. It manufactured parts for bridges. During WWI and WWII it was very active building submarine and ship parts. It also manufactured the steel components for many large and well-known buildings. In 1930 it bought Massilon Bridge and Structural Company of Massilon, Ohio, but its headquarters remained in the Canonsburg facilities. The company was sold in 1986, when the steel industry in the Pittsburgh area was pretty much gone. In 2006 the area was razed and a modern small-manufacturing facility was built to lease out space to smaller companies. The area is now called the Four Coins Industrial Complex, right off of highway 79.
I am only going to model the southeast corner of the very large Fort Pitt Bridge Works complex. That is the part that is visible in the layout I am building at the moment of this structure's construction. In the photo below, the orange rectangle covers the area of interest. You can see the Chartiers creek flowing around the building from the left edge of the photo, down through the bottom of the photo to the right-hand side. The bridge over the creek is how rail traffic came in and out of the complex. As a matter of fact, that same rail was used by other factories located further to the west (the view is toward the south; yes, they had to go through this factory building to get to them!). I have been collecting photos from the Internet ever since I decided to model the PRR's Chartiers branch (2008), so the sources of these photos have gotten lost over time. If I can find the original source, I will attempt to credit them on this page.
Fort Pitt Bridge Works
The Sanborn Insurance map shown below is my basis for the layout of the area that I am modeling. In the map, the large gray area, labeled "17", is the Fort Pitt Bridge Works. You can see the bridge going over the creek in the upper left-hand corner of the map. It clearly shows an indentation in the buildings near the lower center portion of this map. If you look at the photo above, you will notice a slight color change in the roofs of the buildings in the highlighted area. You can just about make out the shape matching this diagram's shape, looking at the slightly darker roofs of the buildings. So, I am speculating that at some point in time, the company extended the buildings to go further southeast. There is nothing between the building and the Chartiers creek, up until the land reaches Buffalo Hill, which is the tree line in the background of the photo above.
Fort Pitt Bridge Works
External Reference:
The photo below appears to be of an earlier aerial photo showing the building closest to the creek (the lighter colored area bordered by trees) as being much shorter than the second building, and the second building having been extended (I presume) as evidenced by the white roof.
Fort Pitt Bridge Works
In the photo below, the buildings are extended, and it appears be of about the same vintage as the first photo above. The Chartiers creek is visible flowing in between the trees in the upper right-hand corner of this photo. Again, you can kind of make out the now-weathered white roof of the second building, and the extensions that both the first and second building must have received at some point in time. These are of a lighter gray color, and highlighted by the orange rectangle I placed on the photo.
Fort Pitt Bridge Works
And so, with all of that in mind, and the 1940s aerial photo shown below, I have decided to model the first building's extension. It clearly shows that the building was placed very close to the creek. In the far lower right-hand corner of this photo you can see the Hazel Mine coal tipple (its incline stretches out across the Chartiers creek). The layout into which this model is going to be placed models the creek until it just about reaches the end of its curve next to the Fort Pitt Bridge Works building, so that should give you an idea of what portion of it I am going to build.
Fort Pitt Bridge Works
With that decision made, I then compared the layout to the above photo, and concluded the overall footprint shape of the building. The diagram below represents the modeled area of the buildings for the layout. Measurements are shown in scale feet. The creek flows at about where the "122" feet marking is.
Fort Pitt Bridge Works
External Reference:
The next thing I needed to figure out was the height of the building. Since the PRR's track ran right through the building, we know it needed at least a 22-foot clearance above the rails (railroad standard at that time). The prototype photo below clearly shows a track entrance running through one of their buildings. There is not enough context within the photo to determine where on the complex this photo was taken. However, there are two turbine or exhaust stacks sticking up, right at about the edges of the factory opening. The "FORT PITT BRIDGE WORKS" letters appear to be set at the center of the roof line. If you look at the first photo at the top of this page, you will see the same style of stacks on the left-most building, near where the bridge crosses the Chartiers creek. Due to the shadow on that center roof line, you can tell there is something on the roof leaving a faint shadow on the sloping roof on the left-hand side. That faint shadow seems to match up with the lettering on the roof of this photo. In the foreground of this photo, it looks like a long gondola is just about to enter (or leave) a bridge. So, I am going to make the conclusion that the photographer was standing on the east side of the Chartiers creek with the camera aimed at the across-the-bridge factory entrance. The tree must be one on the edge of the creek. The gondola on the track on the left-hand side of the photo must be on a track that is part of the Hazel Mine complex. Given that assumption, I should be able to determine the overall height of this building, as it is the other end of this very building that I am wanting to model.
Fort Pitt Bridge Works
External Reference:
A more modern photo shows part of the complex in the background, giving the overall impression of just how tall these buildings must have been. Note that in the 1970s, the Chartiers creek was relocated to be right next to the train tracks, so the bridge shown in this photo is not the same bridge as the one in the photos above. Follow the link on the right to see the aerial view of the bridge shown in this photo (you may have to zoom in a bit on the map to see it).
Fort Pitt Bridge Works
Using the factory-opening photo above, and having no design diagrams or blueprints to go on, I've decided that the building has exterior walls that are 37 feet tall. Based on the Sanborn map above, I've determined (since it provides a drawing scale) that each building was 66 feet wide. My model will only cover the first building. Using the standard "4 in 12" roof pitch (an assumption), I can calculate that the roof section is 11 feet tall, thus making the entire building 48 feet tall. As with all of my modeling, if I come across more accurate data in the future, I can always rebuild this structure.
Since this building is going to be quite a large model, it needs to have a solid base. I decided to build the core out of 1/4" plywood. However, plywood that thin still warps a bit, so I reinforced the interior with some scrap wood, to make sure the two walls are, and remain, at 90 degrees, and that the long wall remains straight. The walls were cut to the scale dimensions mentioned above.
Fort Pitt Bridge Works
The two walls fill the back, right-hand corner of the layout along the creek.
Fort Pitt Bridge Works
That was easy enough, but a sloped roof is where I needed to spend some time thinking about how to make that. The roof's angle is 18.4 degrees. I cut a strip of wood to that approximate angle on the tablesaw, and glued it to the end of the side wall. The first roof panel was also cut out of 1/4" plywood. I wanted its end to be flush with the side wall. So, in this photo you can see two metal weights held in position by two C-clamps. That way the roof could be forced against the metal weights, and I would know for sure that they would be flush. Note the small scrap piece of wood glued to the underside of the roof panel in the foreground of the photo.
Fort Pitt Bridge Works
I could use that to clamp the roof panel against the metal weights. With the panel in place, I carefully applied wood glue to where the roof panel touched the top of the long wall, as well as glue it to the top of the strip of white-painted board.
Fort Pitt Bridge Works
That assembly was, of course, very fragile, but it did guarantee me a good fit of the roof panel. Two additional reinforcement pieces were added, as shown in this photo. The compound angle of the roof panel where it will meet the backdrop was too hard to figure out. So, after the wood glue had cured on all the reinforcements, I took the building to the table saw, and cut the angle into the roof panel. Not easy to do, but I got it to fit correctly.
Fort Pitt Bridge Works
With the one roof panel in place, I then determined that the other half of the roof panel could still fit between the model and the backdrops of the layout. After some calculating, measuring and cutting, I then had the other half of the roof panel for the first building. It was just free-floating in mid-air, so I cut a piece of scrapwood to hold it up. At this point is all just held up with some wood glue, so that the roof panel would sit exactly where I want it to. I could cut one small piece of roof panel for the second building's roof, but, after test-fitting, I realized that it wasn't going to be visible on the layout, so why bother.
Fort Pitt Bridge Works
I filled the gap between the two roof panels with a healthy bead of wood glue, and let that dry overnight.
Fort Pitt Bridge Works
Of course, reinforcement is absolutely necessary for such a delicate bond. I cut two pieces of plywood with the appropriate angles (a few trials were necessary), and then glued them to the underside of the roof. Due to the odd angles, I had to get creative with the clamping. Metal weights and a full bottle of glue provide plenty of downforce on the one side. I had put several strips of blue masking tape on the other side of the roof to hold the two panels together while I did this work. This photo only shows the one brace, but I installed another one in a similar manner on the other side of the roof.
Fort Pitt Bridge Works
Here is an updated status photo. I found that the support board on the back was just too weak, so I added an angled brace to it. Lots of filing and sanding helped to get close the complex angles here.
Fort Pitt Bridge Works
I had moved the building into the garage, because the next steps are going to be smelly. I am going to cover the wood frame with styrene sheet. I am going to use contact cement, which is just nasty stuff. After the styrene sheet is on there, I am going to paint it with the metallic paint I found at Lowes, shown in the photo.
Fort Pitt Bridge Works
I suspect the building was made out of corrugated sheet metal, but I don't have large styrene sheets like that. Second, I figured the building will be 3 to 4 feet from the front of the layout, so the corrugations will not be visible. I found this sheet of Plastruct N-scale simulated wood board in my supply stash, so I glued it to the short wall. After the glue cured overnight, I used a razor blade to trim the sheet to match the profile of the wood structure.
Fort Pitt Bridge Works
A few years ago I had bought some 24"x18" sheets of styrene at several thicknesses at a local hobby show, so they came in handy, as this building is 23 inches long at its maximum. Similar to the side wall, I glued a sheet of 0.020" thick styrene sheet to the long wall. After that cured, I trimmed it to fit the short wall's sheet, and the top and other edges. For the roof panel, I used 0.040" thick styrene (that's all I had left), but I wanted the roof to extend over the walls by a scale one foot. To attach this panel, I placed a lot of shish-kabob wooden skewers on the roof's contact cement, and using a scale one-foot wide piece of stripwood, lined the short side of the styrene sheet up with the short wall. Then, one by one I could remove the skewers and permanently attach the roof styrene sheet. A bit stressful, but it came out OK. It was then a matter of trimming all of the other sides and the roof peak to shape.
Fort Pitt Bridge Works
After I had built the wooden framework of the building, I placed it on the layout. It turns out that the second roof panel is not visible from the normal viewing angle. So, I didn't want to waste precious styrene on it. However, I did want to model the roof top, so I cut a two-foot strip of styrene, and clamped it to the first roof panel's styrene. Then used regular styrene cement to attach it.
Fort Pitt Bridge Works
I then delicately glued a second strip on the back roof panel. It took a bit of blue masking tape to get it into position and stay there while the styrene cement cured. On the wooden side, I simply applied a bead of Aleene's Tacky glue, which should be enough to keep that strip in position.
Fort Pitt Bridge Works
With some delicate cutting and filing, I got rid of the excess material, and we have the final model built.
Fort Pitt Bridge Works
I then applied three coats of the paint to the model, and let that cure overnight. The paint is meant to appear a bit blotchy, which I thought was a bit of a neat weathering affect. I am happy with the result, especially at a distance. The paint left a shiny surface, so I sprayed the whole model with a coat of Testors Dullcote. And below is the completed model. I placed an Artistta S-scale figure next to it, so that it conveys the enormous size of the building.
Fort Pitt Bridge Works
The building will be permanently glued to the module in this approximate position. The back of it will remain open when the backdrops are not installed. This makes it possible to add a factory sound module in the future.
Fort Pitt Bridge Works
I also plan on adding vertical streaking weathering to the model, to age it a bit and also to enhance the illusion of the vertical corrugated sheet metal. This was a fun project to build. It took me a leisurely two and a half weeks of modeling time to make, and a few hours on a Saturday to come up with the estimated dimensions.
Fort Pitt Bridge Works