METHOD AND MACHINE FOR MAKING MOULD CORES

A method of making mould cores by means of a coremaking machine consists in preparing a core compound (7) with subsequent manufacturing of a compound specimen to determine the core compound hardening duration by measuring its electrical conductivity before and after its hardening. The value of its electrical conductivity is then measured by means of a measuring logical unit (29) receiving the corresponding signal from a pick-up (13), that value being determined simultaneously with the value variation range during the core compound (7) hardening process in the core box (3). When the electrical conductivity reaches the level corresponding to a hardening degree ensuring the required strength quality of the mould core, the latter is removed from the core box (3).