This video sequence was filmed by Tony Meades in the early 1980s at the now-defunct Rother Ironworks at Rye in East Sussex. The mould is being formed using casting sand that is tamped down and then levelled by eye before another fireback is used as the pattern and placed onto the sand to leave a negative impression. When it has been lifted out the edges of the mould are built up to form the depth required into which the iron (or in this case steel) is poured.
The next sequence shows the casting process where some other open fireback moulds are being filled with molten metal. To avoid the metal displacing the casting sand (which has been allowed to harden and coated with a graphite compound), the metal is poured through an aperture at the corner of the mould. Many early firebacks show excrescences on their surfaces where metal poured directly onto the decorative impression has dislodged the casting sand and spoilt the casting.
A third sequence shows sand being distributed over the metal cooling in the mould. This will slow down the cooling and render the metal less brittle.
Finally the fireback, the mould for which was being prepared at the beginning of the film, is revealed.