Many types of engineered surfaces have been observed to exhibit a frac
tal geometry. In some cases, modeling the generation of the surfaces p
redicts this and provides correlation between the dimension and histor
y and properties of the surfaces. The complex process of machining pre
cision surfaces does not yet lend itself to such detailed modeling, bu
t observations of the correlations between production methods and surf
ace dimension, independent of material type and hardness, offer encour
agement. (C) 1998 Elsevier Science Ltd.