An embedment device includes a first integrally formed elongate shaft
rotatably secured to the support frame and having a first plurality of
axially spaced disks axially fixed to the first shaft, a second
integrally formed elongate shaft rotatably secured to the support frame
and having a second plurality of axially spaced disks axially fixed to
the second shaft, the first shaft being disposed relative to the second
shaft to be horizontally aligned and so that the disks intermesh with
each other, and wherein, when viewed from the side, peripheries of the
first and second pluralities of disks overlap each other.