he use of quadric surface patches to form a continuous approximating surface to
given curved surfaces was discussed in a paper by Baart and McLeod. A method was proposed
for the construction of continuous patches on a covering mesh of conic segments, where each patch
consists of three quadric subpatches, and each conic boundary segment interpolates three points on
the given surface. This construction is not unique, and in this paper we investigate the effect of
various combinations of the parameters on the resulting quadric patches. We also prolxme a method
that will ensure that, were the given sculptured patch itself quadric, the appruximation will be ex