bc potters

Volume 39 Number 5

Bob Hamm
Slip, Dry and Stretch

Al a recent show, | put a grouping of chocolate slip
wases in the center of my display. When customers
saw them, they invariably walked over and quietly
ran their fingers across the surface and commented
they couldn't resist touching the vases.

These pots have tactile surface qualitics that should
be experienced and enjoyed. Chocolate slip vases
belong to a group I call
slip stretched pots.
They are made in a
range of colours and
surface finishes from
dry to high gloss. The
different colours and
textures are produced
with a vanety of clays,
slips, stains, and
Blazes, The manipula-
tion of materials and
process can result in
fine networks of hair-
like scratches, the
crustiness of a dried
riverbed, or the fibrous
quality of tree bark. My
chocolate slip beads up when
fired, and when the thickness
is just right, it forms strands
of beads trailing side by side
across the surface of the pot.

«44S om

There must be imperfections
or texture in the clay, on the
surtuce of the clay, or in the
coloured slip coating to cre-
ate these surface qualities. I
stunt with a wel cylinder ei
ther textured or smoothed
with a rib. The surface is cow-
ered with a colour Coat of ox-
ide, stain, or slip applied with

_—

blue

15.2 x 15.2.cm

Bob Hamm vase 2002, surface dry brushed
vertically then airbrushed with iron stain. 21.6

a large brush or by spraying. Contrasting textures
on the clay surface and colour coat will result in a
mare complex surface, The bolder the initial tex-
ture, the bolder the final result.

A propane torch is weed te dry the outside skin of
the pot, while leaving the remaining wall of the
pot wet, The intense heat dries ridges and thin spots
in the coating, leaving
softer arcas that open
and break when the
pot is stretched. The
cylinder is stretched
without touching the
outside surface, forc-
ing the outer skin to
crack and form fis-
sures, If heat is ap-
Plied as soon as
breaks appear, the sur-
face and edges of
those breaks will dry
slowing the formation
of new breaks. This
forces [he pot to ex-
pand at the initial breaks.
With repeated heating the
result can be the formation
of wide and deep fissures,
if the wall is thick enough.
There is a sense these pots
contain an inner energy that
expands and stretches them
to its own identity.

see Bob Hamm page ft

slip brushed over vertically;
fedart terra sigillata rabbed into bexture.