Wax model

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    This is a small 14th century hand gonne or cannon, cast using techniques described by Birrenguccio in Pyrotechnia from the 15th century.

    This is the wax model, turned on a lathe, just prior to attaching of the sprue. The sprue cup is made of wood and covered in wax to facilitate removal during burnout. Since this gonne was so small, it was not built on a wooden spindle, but simply turned out of a wax cylinder.

    The sprue cup was attached to the model by heating the projecting pins and pressing it on. It was then coated in successivly coarser layers of loam. Iron wire armature was added near the end of layering. The final wall thickness of the mould was about 1".




    Small 14th century hand gonne casting

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    The cupola was set up with 10 lbs of gunmetal and the mould burried in sand in a pit underneath it. When the metal was molten, the cupola was tapped and the metal poured out into the mould underneath.




    Fresh casting

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    After brushing away the mould material. Some surface roughness, but no major flashing or mould breakage. The small mould to the side is an arm of a folding balance and is unrelated.For this first attempt, in order to cut down on complications that could go wrong, and because I want to actually shoot this, I did not set a core for the bore, which would have been done in the 14thc. I will bore this out on a metal lathe. Solid castings were not actually done until the 18th century due to limitations in boring machinery.

    Here's a video of the pour from the cupola



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