Note: This is a "WORK IN PROGRESS" article. New material will be added as construction progresses. I have uploaded quite a few photos and will add titles and descriptions for them as time permits.
The Prototype
The Choctaw Coal and Railway (CC&R) Company is a small narrow gauge branch line that operates on a shoestring budget. Most maintenance is done in-house at the company repair shed, a simple timber-framed structure with board and batten siding resting on a stone foundation. The structure contains a single-stall repair bay, a machine shop, and a forge area. The roof is a combination of shake shingles and corrugated metal. The structure is approximately 54 feet long by 38 feet wide.
The workers perform minor locomotive overhauls, build and repair rolling stock, and maintain the equipment and tools used by the track gang and the coal miners. The repair bay is capable of holding any of the CC&R locos. An overhead hoist allows heavy parts to be moved between the repair bay and the machine shop. Most of the shop machinery was acquired second-hand. The machines are driven by belts connected to overhead line shafts powered by a stationary steam engine located adjacent to the structure. The repair shed contains a forge area where the blacksmiths keep busy making and repairing parts.
The Model
The model is built to the scale of 15mm = 1 foot or 1:20.3 scale. It is a free-lance composite of various structures and does not represent any specific prototype building. It represents a generic 1939 era structure built with locally available inexpensive materials. Although it represents a small prototype, the model is fairly large (about 32 inches by 24 inches.) The model is designed to be weather resistant for occasional outdoor use. It is mounted on a solid base made from PVC and acrylic to allow easy movement between the layout and indoor storage.
Design
I designed the model using a 2-D computer drawing program. This allowed me to go through multiple variations until I was happy with the overall design. I made a mock-up of the building walls from foam-core illustration board to help finalize door and window placement, to establish the roof geometry, and to layout the interior work areas to match the machinery I planned on using. When I was totally satisfied with the design, I created a complete set of scale plans for the structure and printed these on sheets of 11” x 17” paper. I taped the sheets together as needed to create full sized templates for assembly.
Materials
The structure was built almost entirely from cedar lumber using board-by-board construction. I bought a quantity of cedar fence boards at Home Depot and stacked them in my workshop for a few months, allowing them to dry thoroughly. These fence boards are 5/8” thick x 4" wide x 72” long. I cut them into 24” lengths and ran each piece through a power planer multiple times to smooth the surfaces and to obtain a consistent 10 mm thickness (8 scale inches in 1:20.3.) I ripped the pieces to final size with a Dremel 4” table saw using an 80-tooth carbide blade to make the 8” x 8” posts and beams, the 8” x 14” beams, and the 8” x 3” floorboards I purchased scale 4” x 8” and 2” x 8” cedar lumber for the wall framing, rafters, trusses, and interior work benches from Ozark Miniatures. I purchased assorted widths of 1” and 2” thick cedar boards from Smith Pond Junction for wall sheathing, battens, window frames, and corner trim. The lumber from Smith Pond Junction is actually 1:24 scale so these boards are closer to ¾” thick and 1½” thick, respectively, in 1:20.3 scale.
Construction
The walls were built-up from 8” x 8” posts and sills, 4” x 8” studs and horizontal braces, 1” x 12” vertical sheathing boards, and 1” x 2” battens. Large 8” x 14” beams provide support along the center length and above the repair bay doors. These doors were built-up similarly to the walls and have operating hinges. The floor boards are 3” x 8” planks on 8” x 8” floor joists.
The floor in the forge area of the building is dirt. I shaped a wood block to represent the brick forge, covered it with Plastruct styrene brick sheet , and rubbed gray paint into the mortar joints. The hood over the forge was fabricated from brass sheet. The smoke stacks were made from pieces of telescoping brass tubing.
Windows and small doors are resin castings that have been modified with cedar casings and frames. I used .030” acrylic sheet for the glass panes. The roof of the repair bay is split cedar shakes from Smith Pond Junction. The roof of the machine shop is corrugated metal panels. The roof materials are attached to 2” x 6” spaced sheathing boards supported on 4” x 8” rafters. I made the corrugated metal roofing panels from aluminum soda cans. I cut the individual panels to size with tin snips, heated the pieces in an oven to soften them, and used a paper crimping tool to create the corrugations. The roof sections are removable for access to the interior.
The bottom sills and the floor joists rest on a subframe made from ¾” x 1 ½” (actual dimensions) PVC. The exterior perimeter of the PVC subframe is covered with Plastruct stone sheet.
Construction methods included the use of Titebond III wood glue, a 23 gauge pneumatic pin nailer, epoxy, E-6000 adhesive, acrylic adhesive, silicone caulk, and CAA “super-glue.” Brass and white metal parts were darkened with a chemical blackening solution before being painted. I used acrylic paints on the wood, resin, and metal components. The wood floor was “aged” with ashes and an alcohol/India ink wash. Rail is Code 215 aluminum painted with Krylon Ruddy Brown primer.
The building exterior is painted a faded yellow with brown trim. The interior walls and shake roof were left as natural unpainted wood and weathered with alcohol/India ink washes. The corrugated metal roof panels were painted flat gray and then dusted with various powdered pigments to simulate weathered galvanized steel. All exterior surfaces except window panes were over-coated with Krylon clear matte finish for moisture and UV protection.
Details
The boiler, steam engine, lathe, hacksaw, drill press, grinder, hoist, and overhead line shafts were built from Western Scale Models kits. The winch, crane car, and tool car were built from Ozark Miniatures kits. Numerous accessories, tools, piece parts, figures and general clutter were placed throughout the structure. These include both purchased and scratch-built items.
Posters, calendars, and other interior wall decorations were downloaded from the Internet, scaled to proper sizes, printed on a laser printer, and glued to the walls. Exterior signs were generated on the computer, printed on a laser printer, affixed to wood backing, and mounted to the structure walls and roof.
Interior furnishings include various workbenches, shelves, tables, and stools made from cedar strip wood. Anvils in the forge area are mounted to wood bases cut from tree branches. Dirt, grime, oil, grease, soot, and metal filings were liberally applied to give the structure a well-used but reasonably maintained appearance.
Summary
Total time for the project will be approximately 500 hours spread out over nearly a year. This includes developing the basic and detailed designs, assembling the various machinery kits, cutting the lumber, designing and building the electrical circuits, assembling and painting the structure, and installing the interior details. This is a fun project that allows me to utilize some craftsman construction techniques on my outdoor large scale layout that are normally reserved for indoor scale model railroaders. The repair shed will provide a focal point and helps to set the overall theme of my layout … namely a small backwoods narrow gauge branch line, barely hanging on from day-to-day, and surviving only by the ingenuity and dedication of its workers.