To reproduce this gate from an original it was laid in the sand and tampered down sand to the centerline of gate.
Here you see the gate being lowered into the sand box, we are using an original gate as the pattern. The sand is rammed to the center line and the gate is carefully removed. The cavity left then becomes half of the mould for the new gate.
The process is repeated to create a top half and the mould is closed. The hot metal is then allowed to flow into the cavity in the sand.