  We present 1D numerical simulations aimed at studying the hot-flasher
scenario for the formation of He-rich subdwarf stars. Sequences were calculated
for a wide range of metallicities and with the He core flash at different
points of the post-RGB evolution (i.e. different remnant masses). We followed
the complete evolution from the ZAMS, through the hot-flasher event, and to the
subdwarf stage for all kinds of hot-flashers. This allows us to present a
homogeneous set of abundances for different metallicities and all flavors of
hot-flashers. We extend the scope of our work by analyzing the effects in the
predicted surface abundances of some standard assumptions in convective mixing
and the effects of element diffusion.
  We find that the hot-flasher scenario is a viable explanation for the
formation of He-sdO stars. Our results also show that element diffusion may
produce the transformation of (post hot-flasher) He-rich atmospheres into
He-deficient ones. If this is so, then the hot-flasher scenario is able to
reproduce both the observed properties and distribution of He-sdO stars.
