There is evidence here of a McCormick reaper in use at Hatch Warren Farm near Cliddesden in about 1900.
I am building the 1903 version using these resources, plus others, as the basis for the model.
McCormick Brochure 1
McCormick Brochure 2
The machine appears quite complex with pulleys, wheels and chains on view all over the open framework. Modelling these intricate parts is nigh on impossible in 2mm scale. What I hope to capture in the model is a fair representation of the machine by modelling the most visible parts when viewed from a distance of about 2 feet.
I'll start with the 'reel'. This is a rotating hub of 6 slats that neatly lay the stalks of wheat cut by the sickle onto the reaper conveyor platform.The 1903 reaper was available in 5', 6', 7' and 8' wide cutting lengths. I am modelling the 5' version so the model reel (photo) is about 10mm wide and 10mm diameter.
It is made from brass strip for the slats and copper wire for the supports with a copper wire spindle, all soldered together.
Two techniques I developed to ease the assembly ready for soldering. For a slat assembly a slat support (wire) is formed into the asymmetric U shape and offered up to the slat. The ends of the wire are looped one turn around the slat. This holds the wire firmly in place whilst a hot iron and solder is applied to the joints. Repeat for the other slats so we have 6 separate assemblies.
Next, get a flat circle of BluTack, or similar. This is used to hold the spindle and slat assemblies together prior to soldering. The spindle is first pushed vertically into the BluTack. Each slat is then married up to the spindle and held in the BluTack ensuring parallel orientation to the spindle and 60 degree separation between each other. The soldering iron is applied to the spindle and the solder fed into the assemblage of spindle and slat supports.
Simple for such a small assembly when you know how.
To Part 2.
David
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