Bipolar nebulae constitute a large subset of the planetary nebulae population. We present the first results of a project aimed to map physical parameters and chemical abundances across extended planetary nebulae with bipolar structure. These results can be used as input and constraints into numerical simulations in order to reproduce their properties in the visual band of the spectrum. This provides a way to examine the non-homogeneity present in this kind of object, as well as a tool to derive their intrinsic properties, like tridimensional geometry and matter distribution, central star properties, distance, and other properties in a self-consistent way. Here we show our results for two of these objects: IC 4406 and NGC 6572.
