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kiln wash. itc, zirconium oxide wash

updated mon 23 feb 04


Anne Webb on sun 22 feb 04

was curious if anyone out there.. at least on this list.. has used a
zirconium oxide wash for the inside of their kiln vs itc. i know itc works
but has a tendency to flake off and need frequent recoats.

curious how effective the zirconium wash is in saving brick linings of kilns
in salt/wood, recommended thickness of application, how frequently you like
to reapply it, ratio of water:zirconium in wash, etc etc. any
success/disaster stories.

still sunny today on the gulf coast

Stay informed on Election 2004 and the race to Super Tuesday.

John Anthony on sun 22 feb 04

I coated my wood/salt kiln with a zirconiium oxide wash before
the first firing, at Will
Ruggles' recommendation. Basically brushed it on with a whitewash brush.
I then recoated lightly after that and the second firing. I think if
it flakes off it probably went on too
thick. I haven't had any flaking and after seven firings there is very
little deterioration
of the softbrick in the chamber. I didn't do shelves or furniture,
though I do dip about 1" of my posts in a slightly
thicker wash when loading.
I put it on the kiln skim milk thick, and brushed a couple of coats,
till the brick was visually obscured by the
coating. Definitely not thick enough to chip or flake.
I have touched up a few times after recent firings, but all in all it's
holding up well.

John Anthony

Lee love on mon 23 feb 04


I used kaolin and alumina to coat the walls of my wood kiln,
which has a softbrick interior. I didn't coat the arch, except where
it overhangs the firebox opening and also where it overhangs the door
bricks. I looked at Euan's kiln and saw where most of the ware was
from the flame. I figured, if I didn't put any on the arch over the
ware area, I wouldn't have to worry if any flaked off, it would miss
landing on anything.

I used 60 alumina/ 40 kaolin. I put it on two ways:
brushed and sprayed. I think I got the brushing on too thick, but
the spraying worked really nice. I sprayed about 3 really thin coats
twice, once before the first bisque firing and then again after the
first glaze firing. After the bisque, the coating is still powdery
and doesn't get hard until after the glaze firing. Where the
brushing flaked off, at the entrance of the flame from the firebox, I
touched up by spraying.

Lee In Mashiko

"With Humans it's what's here (he points to his heart) that makes the
difference. If you don't have it in the heart, nothing you make will
make a difference." ~~Bernard Leach~~ (As told to Dean Schwarz)