Self-setting moulding aggregates are intended for jobbing or small-batch production, as already noted above. Employing special designed machines, this binder system can also be used in a higher scale production of cores if a very short setting time is used. The moulding process requires dosing of moulding aggregate for each single core and extremely rapid processing of each dose. This method is an alternative to the cold box processes and is referred to as the Fascold process. The first of such methods is the Gisag Cold-Box process, developed in the East Germany in 1968.
The process is based on a special high-speed mixer. Two primary screw mixers work in parallel: one mixing the base aggregate and resin, and the other mixing the base aggregate and a fast acting hardening catalyst. The premixed components are then discharged together into a high-speed mixer in pre-determined amounts for a single core. The resultant mixture is subjected to tumultuous mechanical agitation for a short mixing period measured in seconds. The prepared dose of the aggregate is immediately shot into the core box, where an exothermic setting reaction takes place. The binder sets fast enough to discharge the core from the box in less than a minute, often in a period as short as in 40 seconds. The produced core may be set into the mould after 5 to 15 minutes.