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weighted assessment value is 0.1478 in MOORA of experiment no. 20. Thus, the
twentieth experiment gives the best multi-performance characteristics of the CWEDM
process among the 27 experiments by the MOORA technique also by the GRA technique.

Besides, the confirmation tests carried out to verify the adequacy of the theoretical
predicted model that was developed. It was found that developed models can predict the
MRR and SR accurately within a 10 % margin interval. The margin error obtained from all
responses studied in this research work were all accepted as the results indicated lower
than the allowable set of margin error. In this research, the margin error was set below
10%. The confirmation test shows that the errors associated with MRR are within the
range of 0.16 % ~ 1.76 % and with SR are within the range of 0.33 % ~ 1.62 %.
This CWEDM is possible to use in many industries for cylindrical machining on difficult
material without evade principle of normal WEDM.

Key words: CWEDM, synchronized rotary motion control, cylindrical machining, turning,
GCr15, design expert, GRA, MOORA.

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