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woodfire glazes and claybodys?(longish)

updated wed 14 feb 01


steve dalton on tue 13 feb 01

Hi Andy,
Sorry, but I would've put my response to your questions sooner, but I've
helping my uncle with his farm(he broke his back awhile back).

I'll answer your questions in order to the best of my expierence and
especially since I've only been wood-firing for a year and half now.

1. I grabbed my copy of Fred Olson's 'Kiln Book,' to figure this one out.
Fiber Board
would be a dual purpose material in kiln building. The first, secondary
The second and the most important, reduce the amount of air pulled into the
through the cracks in the brick work. You want the air/draft to come from
the fireboxes,
where you have more control.

I would say Flex Board is a specialty item from a 'Major' supplier or even
the manufacturer.
I have never built the 'Fast Fire,' so I'm not sure on it's importance, all
I can say is to play
around with or without it. If you decide not to use it, I would suggest
mudding up the outside
kiln with a fireclay/sand/itc mixture or spraying the inside with itc

2. Depending on your cones, I've fired regular cone 10 glazes
in my wood-kiln with very good results. All we're doing is adding
ash, flame and a longer time when we fire with wood. Some glazes
are further enhanced with the addition of fly ash. From my firings
lighter glazes, ie white or off-white benefit the most. I've even tried
commercial glazes for testing and I've also recieved very good results.

Ash Glazes that I've used...

Ash(Alder/mixed, etc) 40%
Custer(Potash) 40%
Whiting or OM4 20%

This is a standard glaze from various books. I've even
used Dolomite for the Whiting and Kona F4(Soda) for
the Feldspar. Color ranges from a Translucent Grey to
a Greyish White, depending on atmosphere and thickness.

Iron Oxide banding looks wonderful on this glaze with bleeding.

Here's another basic glaze open for expiermenting...

Ash(Any) 50%
Any Slip Clay(Albany, Alberta, etc) 50%

Depending on the Slip Clay, your fired color will vary
but this is nice semi to very runny glaze.

3. I've been using Laguna's Rods Bod alot, mainly for the
iron bleed through, but there are several bodies out there
that would look even better. Laguna's B mix 10 (I think is the name),
flashes very well. Scott's(produced locally) flashes very well
and is a good throwing stoneware.

I've even pugged small amounts of ^6 clay into my ^10 clays, just to get
more of lower melting ingredients into the mix.

What you want in a clay body is a raised level of Custer or
the addition of Helmar Kaolin.

If you've gotten this far...I would suggest Jack Troy's "Wood-Fired
and Porcelain." In there, you will find more info about clay bodies and
with good several recipes.

Steve Dalton
Clear Creek Pottery
Snohomish, WA

>From: rohde
>Subject: woodfire glazes and claybodys?
>Date: Tue, Feb 13, 2001, 11:29 AM

>i have 3 different Questions for all of you....
>1. is i am building a fast fire wood kiln and i need to know what the flex
bored is used for and do i really need it??????
>2. i need woodfire glazes?
> ash glazes
> etc......
>3. and are their any claybodys type that work really well in woodfire.
> if so what do i need to make them...
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