  We have studied self-sustained, deformable, rotating liquid He cylinders of
infinite length. In the normal fluid $^3$He case, we have employed a classical
model where only surface tension and centrifugal forces are taken into account,
as well as the Density Functional Theory (DFT) approach in conjunction with a
semi-classical Thomas-Fermi approximation for the kinetic energy. In both
approaches, if the angular velocity is sufficiently large, it is energetically
favorable for the $^3$He cylinder to undergo a shape transition, acquiring an
elliptic-like cross section which eventually becomes two-lobed. In the $^4$He
case, we have employed a DFT approach that takes into account its superfluid
character, limiting the description to vortex-free configurations where angular
momentum is exclusively stored in capillary waves on a deformed cross section
cylinder. The calculations allow us to carry out a comparison between the
rotational behavior of a normal, rotational fluid ($^3$He) and a superfluid,
irrotational fluid ($^4$He).
