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This is the subject of the build: This aeroplane, under the grand title 'Air Fleet of the Northwest' provided important support to the faction of the Constitutionalists led by by Alvero Obregon during 1913 and 1914. The aeroplane, along with the services of a professional pilot and mechanic, was acquired from the Glenn Martin Co. in California for $5,000, and smuggled across the border with Arizona in circumstances attended with a more than usual ration of skullduggery. I freely acknowledge that a good deal of what I am doing in this build is conjectural, as there are no drawings available, nor have I even seen stated dimensions for this particular aeroplane. There is a decent photographic record of the machine, though, and Mr. Martin's designs at this time were largely copies of Curtiss aeroplanes, albeit tweaked somewhat. I am operating on the courteous assumption that basic elements, such as aspect ratio, were not significantly altered by Mr. Martin and his workmen. Modelling this aeroplane required a couple of important sub-assmblies, difficult in themselves, which I have already gotten in hand. First the motor, a representation of an early Curtiss V-8: Its assembly may be found in this tread: The second is the provision of spoke wheels, three of which are required. The matter was complicated by the small size of the wheels. Their construction, and the method by which they were made and the tools and materials used, can be found here: With these items in hand, and after some study of photographs, and period drawings of various contemporary Curtiss machines, I settled on dimensions and pattern for the wings. In these old 'flyers' produced by early designers in the U.S., the wings are the main structural element. Aside from motor and associated plumbing, there is not much besides sticks and strings (though there are a lot of those, the strings particularly). A rib spacing of 4.5mm provided a wing-span of 180mm, with a little fudge at the tips, scaling up to about 12.9 meters, or about 42' 6", measuring flying surface tip to tip, which is within the range of long-span Curtiss 'flyers' Mr. Martin would have been copying (spans given for Curtiss machines, by the way, often give the distance from aileron tip to aileron tip, not the span of the actual flying surfaces). I used the five foot basic chord usually employed by Curtiss. The 'ear' wingtips are Mr. Martin's; Cutiss wingtips generally were squared and ended at the outer bay of interplane struts. The wings started out as blanks of .030" styrene sheet, cut to measure and bent by hand. After bending, they were sanded to a smooth curve surface. On the concave undersurfaces, this was done with heavy grit sandpaper fastened to a large bottle (about 4" in diameter), with a such paper on a smaller bottle (about 1" in diameter) used for final shaping. The upper surfaces were done with heavy grit sanding sticks. Once the shape was in hand, I began laying out the ribs. I managed to cut myself a little cutting these out, but am of the school that blood sacrifice to the modelling deities secures some favor in a build.... Once the ribs were laid out, I 'broke the plane' between them with a narrow 'swizzle-stick' sanding stick, and the curved edge of a #10 blade used as a scraper perpendicular to the plastic. You don't need to go very deep, just enough to leave a 'ridge' readily apparent to your finger-tip brushed along the surface. Once this had got a couple of coats of white primer, and a couple of coats of Future, the next step was applying rib tapes, quite literally in this instance: I used 1/64" pin-stripe cut masking tape. Fiendishly useful stuff, and I am beginning to look for resupply (the company is 'Line o' Tape') as I am now down to about half of my last 240' roll of it. As will be seen in the photographs, Martin used a dark tape (possibly even blackened strips of wood or cane) to secure fabric to the ribs. I darkened the tapes with an ordinary #2 pencil. This then received two more coats of Future, which helps fix th tape down firmly, and seals the pencil marking. On the undersurface, it is only necessary to draw in the tapes, there is no need to 'break the plane'.... After this, I have begun to paint the fabric.... ey andan Again, it will be clear from the photographs Martin used a pale fabric indeed. I have used a mix a light grey and tan, quite thinned, and brushed on between the ribs. It will get a couple more coats of this, but I will say the coverage looks more uniform to the eye than it does under flash and a macro lens. Next step will be picking out which wing will be which, and beginning to assemble the motor and undercarriage to the piece chosen as the lower wing....