When the foundry proceed the lost foam casting process, the sand is not bonded and a foam pattern is used to form the shape of the desired metal parts. The foam pattern is "invested" into the sand at the fill & compact process station allowing the sand into all voids and supporting the foam patterns external form. The sand is introduced into the flask containing the casting cluster and compacted to ensure all voids and sapes are supported.

• Mold foam pattern making.
• Age pattern to allow dimensional shrinkage.
• Assemble pattern into a tree
• Build cluster (multiple patterns per cluster).
• Coat cluster.
• Foam pattern coating.
• Compact cluster in flask.
• Pour molten metal.
• Extract cluster from flasks.