For sandcasting, you don't put the piece into the sand but rather put the
sand into the mold with the piece on the bottom. Then pack the sand well
and you should be set.
Splashing the metal in does tend to destroy the mold rather rapidly as the
metal is rather heavy and erodes where it hits. If you have to splash, use
a thin stream and don't allow a large drop of the metal.

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Why isn't there an Ozone Hole at the NORTH Pole?