  In this paper (the first of a series) we describe the construction of fixed
point actions for lattice $SU(3)$ pure gauge theory. Fixed point actions have
scale invariant instanton solutions and the spectrum of their quadratic part is
exact (they are classical perfect actions). We argue that the fixed point
action is even 1--loop quantum perfect, i.e. in its physical predictions there
are no $g^2 a^n$ cut--off effects for any $n$. We discuss the construction of
fixed point operators and present examples. The lowest order $q {\bar q}$
potential $V(\vec{r})$ obtained from the fixed point Polyakov loop correlator
is free of any cut--off effects which go to zero as an inverse power of the
distance $r$.
