Raymond Jimison on sun 26 jun 11
I seem to have an issue with my Laguna white crackle glaze. It bubbles and =
crawls..=3DA0 At first I wasn't sure if I was over firing, under firing it,=
=3DA0applying to thick, etc.=3D0A=3DA0=3D0AI am using a pyrometer, and firi=
en 1800-1835 F.=3DA0 When=3DA0the glaze=3DA0is too thin, besides the obviou=
aks, it has small black spots and does not crackle.=3DA0 I determined this =
s from putting the pot into reduction too fast.=3D0A=3DA0=3D0AWhen the glaz=
e is a=3D
normal thickness, it will start to crawl and pull away from the pot.=3DA0 =
is glaze always breaks and curls when copper carb is added too it.=3D0A=3DA=
When to pot is pulled at a lower temperature, say 1700F,=3DA0 I get really =
od crackle but still a little crawling though not as much.=3DA0 With copper=
arb in it, at 1700 it still breaks away.=3D0A=3DA0=3D0AI think it is the gl=
self, and not my technique.=3DA0 The reason I say this is I also have a Lag=
a shinja that is absolutely beautiful.=3D0A=3DA0=3D0AThanks,=3D0ASandra=3D0=
email@example.com=3D0A=3DA0=3D0AI know there are 1000 raku=3DA0 white cracke =
ut there, but before going and experimenting with different combos, I thoug=
ht I would just ask if my conclutions make sense.
paul gerhold on mon 27 jun 11
Explain exactly how you are applying the glaze to get it thick enough. Som=
application methods will exacerbate a glazes tendency to crawl. Are you
dipping, brushing multiple coats, prewetting the ware, etc.
On Sun, Jun 26, 2011 at 8:12 AM, Raymond Jimison
> I seem to have an issue with my Laguna white crackle glaze. It bubbles an=
> crawls.. At first I wasn't sure if I was over firing, under firing it,
> applying to thick, etc.
> I am using a pyrometer, and firing between 1800-1835 F. When the glaze i=
> too thin, besides the obvious streaks, it has small black spots and does =
> crackle. I determined this was from putting the pot into reduction too
> When the glaze is a normal thickness, it will start to crawl and pull awa=
> from the pot. This glaze always breaks and curls when copper carb is add=
> too it.
> When to pot is pulled at a lower temperature, say 1700F, I get really go=
> crackle but still a little crawling though not as much. With copper carb=
> it, at 1700 it still breaks away.
> I think it is the glaze itself, and not my technique. The reason I say
> this is I also have a Laguna shinja that is absolutely beautiful.
> I know there are 1000 raku white cracke glazes out there, but before goi=
> and experimenting with different combos, I thought I would just ask if my
> conclutions make sense.
Steve Mills on mon 27 jun 11