 |
The mould was 36 feet long with a cross section of the rib being 4.5" x 3". The blue machine above the radial pole is the sand mixer. This mixer is computer controlled to allow resins and catalysts to be mixed with reclaimed sand. The temperature of the sand, ambient temperature and speed at which we require it to set are controlled automatically. The sand it produces is used to make the mould, into which we will pour the molten iron. It was imperative to have a flat bed as the iron like water would find its own level, if we were too high at one end the metal would overflow at the other and provide the BBC with a floor of metal. |
|||||||
 |
One of the ribs has already been cast, the box about three feet from
this end on top of the casting is where we poured the metal into the mould.
The second rib is being cast at the far end and the metal can be seen half way along the mould heading towards us. The first casting was freezing as the metal reached the end. For the second cast, the metal was poured into the mould faster which allowed the metal to remain hot as it reached the far end, but this faster pouring created its own turbulence as waves ran from one end to the other and back again threatening to come over the top of the mould. As the waves were about 25mm high we had to stop the pouring and then continue as the waves subsided to a safe level.
|