search  current discussion  categories  kilns & firing - misc 

fire box/gq

updated sun 7 dec 03

 

Imbolchottie@AOL.COM on sat 6 dec 03


I've noticed that some of the best glaze results are happening inside of the
'vessels' I'm making -- mugs or vases. I realize that less air circulating
inside the vessel as opposed to the outside. Large bowls are different; has
more heat circulating in due to shape. For a while there I mistakenly thought I
wanted to saggar fire -- not necessarily so -- I just wanted to fire a piece
within another piece.

My thought was build a large lidded box and put several pieces inside and
fire that in the kiln. Has anyone ever fooled around with this idea? If so were
the results dramatically different from having the piece shelved in the kiln?
Does this 'BOX' reach the true temperature as the rest of the kiln or is it
a cone lower than the rest?

I think it will also cut down on the random blessing from the Kiln Gods
"Where that THAT come from?" I try to vacuum out the kiln before loading but our
vent overhead is really old and deteriorating. I have built a kiln shelves up
to within an inch or so from the vent, trying to keep heat in and also avoid
the buggers (boggers?) that occasionally fall in.

I know this is NOT saggar firing -- due to the absence of organic material
inside the box -- but what is it?

Jonathan in LA
Some cremation tid bits: Not all states require that the body be in a box
which goes into the furnace - Calif., does and the family has the choice from
everything from a traditional casket to pine box to cardboard box -- so in some
states there is wood ash mixed in with the human remains. Furnance gets to
5000 degrees for about 5 hours -- I forgot to ask if all fluids are removed prior
to the procedure.

Hollis Engley on sat 6 dec 03


----- Original Message -----
From:
To:
Sent: Saturday, December 06, 2003 12:37 PM
Subject: Fire Box/GQ


> I've noticed that some of the best glaze results are happening inside of
the
> 'vessels' I'm making -- mugs or vases. I realize that less air
circulating
> inside the vessel as opposed to the outside. Large bowls are different;
has
> more heat circulating in due to shape. For a while there I mistakenly
thought I
> wanted to saggar fire -- not necessarily so -- I just wanted to fire a
piece
> within another piece.
>
> My thought was build a large lidded box and put several pieces inside and
> fire that in the kiln. Has anyone ever fooled around with this idea? If
so were
> the results dramatically different from having the piece shelved in the
kiln?
> Does this 'BOX' reach the true temperature as the rest of the kiln or is
it
> a cone lower than the rest?
Jonathan

Jonathan: Others have no doubt had much more experience than me in saggar
firing. But it happens that I opened the kiln this morning and took out my
first attempt, a saggar improvised from one squared casserole placed
rim-to-rim on another. Inside were five small vases, three porcelain and two
tiny stoneware. Packed them up to their midlevels in sawdust. The results
are intriguing, very black reduction top and bottom, with a wavering white
line in the middle roughly at the level of the sawdust. Much like the
saggar-fired pots of John Leach. I think from the sound of thunking the pots
with my finger that they may have only reached bisque temperature or
slightly above, though the rest of the kiln was fired to ^10. That's more or
less what I expected from talking with people who had fired this way. As I
say, others no doubt have more experience with this, but I thought I'd
mention it.
Hollis Engley
hengley@cape.com
Hatchville Pottery
Falmouth, Mass., where there are eight inches of cement-like snow on the
ground, rain in the air, more snow to come tonight.

John Hesselberth on sat 6 dec 03


On Saturday, December 6, 2003, at 12:37 PM, Imbolchottie@AOL.COM wrote:

> I've noticed that some of the best glaze results are happening inside
> of the
> 'vessels' I'm making -- mugs or vases.

Hi Jonathan,

Are you sure you are not just seeing the effects of slow cooling that
has been so widely discussed here? On forms like mugs and vases the
inside can cool quite a bit more slowly than the outside. If you are
not already slow cooling you might just try that instead of building
boxes.

Regards,

John
http://www.frogpondpottery.com
http://www.masteringglazes.com