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to karin hunt, re: terra-sig

updated mon 23 aug 99

 

terryh on sun 22 aug 99

------------------
karin, appears all my replies came back undelivered. so, i post this =
on-list.

=3E yes, this is how i do.
=3E terra-sig. preparation: i use OM4 ball clay. blend ball clay with =
water,=3D
=3E approximately 1: 2 volume ratio
=3E (approximately=21 not exact) i use an electric blender. if you need =
colored=3D
=3E terra-sig, add underglaze
=3E or metal oxide. in case of metal oxide, better use ball-mill prior to =
add=3D
=3E ing water. leave the mixture
=3E (milk-like texture) in a jar for a day or two.
=3E application: discard the clear top-layer water. apply the terra-sig slip=
=3D
=3E (still milk-like texture, a little thicker)
=3E
=3E to a bone-dry bear surface, using brush. one or two coating should =
suffic=3D
=3E e. if thicker, the coating tends
=3E to flake off sometimes. when the coating start getting dry (white), =
burni=3D
=3E sh the surface w/ smooth stone or back of the spoon or whatever smooth.
=3E bisque firing: bisque fire to O9 to O10. if it gets hotter (as to O5 - =
=3D
=3E O6), the surface will lose its sheen.
=3E smoking: either raku-fire and smoke or saw-dust-fire. you will get shiny=
=3D
=3E black. if you want to keep different shade of black, such as B-on-B, =
leav=3D
=3E e the surface w/out terra-sig, or if it's already terra-sig burnished, =
=3D
=3E then apply regular diluted clay slip to make the surface non-smooth.
=3E for the bears (i don't know how big they are) saw-dust firing may be =
safe=3D
=3E r. but in case you prefer the raku firing, the temperature doesn't have =
=3D
=3E to go so high as to melt raku-glaze. just high enough to create enough =
=3D

=3E smoke. i usually use a pencil mark or china-marker and remove the piece =
=3D
=3E when the trace of pencil (or sign-pen) mark gets burnt off.
=3E well, i hope this will help. good luck.
=3E could you show me how your bears turn out, get darker? if it doesn't get=
=3D
=3E dark enough, it could be a polar bear=21
=3E ciao,
=3E terry
=3E
terry hagiwara
e-mail: terry.hagiwara=40halliburton.com (W)=3B terryh=40pdq.net (H)
web: http://www.geocities.com/SoHo/Cafe/3755