Based on the plan I laid out in A Plan For the Freight House, I decided to create a wooden core of the freight house and then add an outer layer of styrene for the corrugated metal of the shell. For the core my intention was to laser cut walls with window openings from 1/16″ bass wood since I’d have to 2D draw the structure anyway. I’d create three segments separated by the two firewalls. The roof would be made of separate pieces, most likely of basswood as well. The floor is elevated to the height of the ramp, and the structure would sit on the base that I already glued onto the layout a while ago.
Proof of Concept
I soon realized that with all the detail design, I’d have to create a prototype first, unless I wanted to spend a fortune on flawed laser cut walls. So I did create the plans for the first segment with Inkscape, but then I printed them out and cut the walls manually from bass wood. I used styrene parts for the windows and freight doors so my walls were straightforward with no complicated details.
The first segment worked out surprisingly well. For both the small and large windows as well as the freight door, I used Grandt Line parts. The small windows I had to cut and glue from larger windows, and for the freight doors I had to reduce both height and width. As they are also made of styrene, they were easy to cut and glue and with practically no visible seams. I made good progress on the first segment and the result was surprisingly good, so I decided to cut all the wood manually instead of using the laser cutting. Still, I made sure that I made all modifications to the 2D plans first before I’d cut them in wood.
Modeling Corrugated Metal Walls
For the corrugated metal I first considered making my own sheets of corrugated aluminum (using a method for making corrugated roofing based on aluminium embossing sheets) but then realized that it would be hard to create a regular pattern on the sheets. For a styrene-based approach I had two options: the Evergreen Metal Siding (#4526) sheets with .040″ spacing and thickness and the Plastruct Corrugated Siding (#91510) with a similar spacing but only .020″ sickness. I liked the distinctive texture of Evergreen product but cutting it turned out to be much harder than the Plastruct sheet. Since the prototype’s corrugated metal had most likely a much narrower spacing than the 6″ that would correspond to the .040″ I decided to go with the Plastruct styrene sheets. The effects of the linear texture of the corrugated sheets could be achieved as well with the somewhat flatter character of the Plastruct product, especially after weathering.
Before glueing the corrugated metal sheets onto the wooden core, I airbrushed the wooden model with a dark grey. This was important as the dark window frames and sills that contrast with the bright color of the corrugated walls give the building its characteristic appearance. The styrene walls got a good coating of light gray. To make sure that the styrene would sit well on the wood, I used a two component epoxy adhesive.
Building th Roof
Adding a slag covered roof first caused some headaches. My initial plan was to use basswood and to coat it with ballast although I was aware that it could warp. After some testing, I found that thinned down PVA glue (using 70% Isopropyl alcohol) works without deforming the 1/16″ basswood sheets. I had to use the airbrush to apply it, and I’d have to ballast it carefully in several layers. Still, the result was not convincing (see the lighter roof section of segment 3), and I switched to styrene for the roof as well. Ballasting it turned out to be easier, although not completely hassle-free. The glue has to be applied in equal amounts to avoid creating a completely flat and even coat of ballast.
The geometry of the inward sloped roof creates a slightly concave shape which can only be achieved by cutting each one of the 26 half-segments separately and glueing them in place. To emulate the prototype’s transition between wall and roof, I used 2.4 mm wide styrene Zee strips which I painted and glued on top of the walls. This not only creates a small (desired) overhang but also a cradle for the roof segments. I avoided glueing down the roof onto the walls as I wanted to make the inside of the freight house accessible. The roof sections of four to six joined half-segments sit on the framed walls and can be easily removed and put back.
For the moment, I just cut out rectangles for the skylights. They have a very particular shape and so far I haven’t found any product that would fit. It looks like I’ll have to 3D-design them by myself so that I can get them 3D printed. This and a few other odds and ends will have to added over time. For the paved courtyard, I used MonsterModelWorks’ old cobblestone (actually: Belgian blocks) sheets which I painted and weathered. The almost completed freight house looks awesome, however, doesn’t it? And it also works operationally: Almost all of my 36′ and 40′ boxcars, including the ones with sliding doors, make it around the house without touching the walls!