nsm - casting floor

Nice display of sand moulds as used in an iron foundry.
In this case, the lower half of the mould is exposed - the product will be a wheel, as shown standing on the corner, still with the risers and filler attached.
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This didn't seem to be explained, so unless you already know what you are looking at here ...
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I talked about patterns and casting to several visitors whilst taking this group of images.