In the ceramics industry the creation of moulds for new product design, thr
ough the use of rapid machining has become an alternative to traditional te
chniques. During an investigation into the potential of mould creation thro
ugh this technique it was noted that the rate of tool wear while machining
the plaster material was greater when a ceramic plaster; Molda 3, was compl
etely dry, than when moisture was present. The present paper reports on the
causes of excessive tool wear which occurs in the machining of plaster and
how the moisture content of the plaster can have a considerable effect on
the rate of wear. A series of experiments has been conducted to determine t
he optimum level of moisture retained in the plaster to achieve the best ma
chining results. In addition, the method of machining was also investigated
, to determine if this had any relationship with tool wear. BCT/303.