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firing shino, again

updated sat 11 jun 05

 

Gail Dapogny on mon 6 jun 05


I took a blah shino pot and put it in our semi-large gas kiln that we
bisque in, and sure enough it took on a much deeper gold cast. The
bisque took 7-8 hours to fire, then had a 22-hour or so cool-down, as
usual.

Then I took several more shinos that weren't great and put them into
our 18 x 18" little electric kiln and fired to 06. Nothing happened;
the pots stayed the same. The kiln, being small, goes up fast and
cools fast. I figured that this was the reason, perhaps especially in
the cooling phase. But I don't know what's really happening here. Can
anyone give me some expertise on this?
Thanks in advance. Gail


Gail Dapogny
Ann Arbor, Michigan
gdapogny@umich.edu
http://www.claygallery.org/
http://www.pottersguild.net/

Hank Murrow on mon 6 jun 05


On Jun 6, 2005, at 8:14 AM, Gail Dapogny wrote:

> I took a blah shino pot and put it in our semi-large gas kiln that we
> bisque in, and sure enough it took on a much deeper gold cast. The
> bisque took 7-8 hours to fire, then had a 22-hour or so cool-down, as
> usual.
>
> Then I took several more shinos that weren't great and put them into
> our 18 x 18" little electric kiln and fired to 06. Nothing happened;
> the pots stayed the same. The kiln, being small, goes up fast and
> cools fast. I figured that this was the reason, perhaps especially in
> the cooling phase. But I don't know what's really happening here. Can
> anyone give me some expertise on this?

Dear Gail;

I have experienced several results similar to your description. My
theory is that electric kilns fire neutral, not oxidizing.
Shino-firecolor needs some oxidation to develop the reddish color of
ferrite crystals, and most gas kilns can fire in oxidation. Perhaps a
Clayarter with positive ventilation in their electric could get an
oxidizing atmosphere and confirm what is only a hunch on my part. Time
at temperature, however, is always a factor as you suggest.

Cheers, Hank
www.murrow.biz/hank

Hank Murrow on tue 7 jun 05


On Jun 7, 2005, at 3:44 PM, Craig Martell wrote:
>
> Sure it does.

I tend to agree with you.

Hank

Liz Willoughby on tue 7 jun 05


Hello Gail and Hank,
When I first started refiring some of my shinos in my electric kiln,
I only fired them to bisque, and they were not successful. When
touched they seemed to have a "skin" on them, and tiny, tiny, crazing
all over. I did a few tests on going higher in temp. I ended up
going to 1950F, and soaking for 2 hours before turning it off, with
the top peep open. The shino was redder, more depth of color, and
lustred where there was ugly carbon trapping.
Meticky Liz from Grafton, Ontario, Canada
(needing rain badly)


>On Jun 6, 2005, at 8:14 AM, Gail Dapogny wrote:
>
>>I took a blah shino pot and put it in our semi-large gas kiln that we
>>bisque in, and sure enough it took on a much deeper gold cast. The
>>bisque took 7-8 hours to fire, then had a 22-hour or so cool-down, as
>>usual.
>>
>>Then I took several more shinos that weren't great and put them into
>>our 18 x 18" little electric kiln and fired to 06. Nothing happened;
>>the pots stayed the same. The kiln, being small, goes up fast and
>>cools fast. I figured that this was the reason, perhaps especially in
>>the cooling phase. But I don't know what's really happening here. Can
>>anyone give me some expertise on this?
>
>I have experienced several results similar to your description. My
>theory is that electric kilns fire neutral, not oxidizing.
>Shino-firecolor needs some oxidation to develop the reddish color of
>ferrite crystals, and most gas kilns can fire in oxidation. Perhaps a
>Clayarter with positive ventilation in their electric could get an
>oxidizing atmosphere and confirm what is only a hunch on my part. Time
>at temperature, however, is always a factor as you suggest.
>
>Cheers, Hank
>www.murrow.biz/hank

Hank Murrow on tue 7 jun 05


On Jun 7, 2005, at 5:16 AM, Liz Willoughby wrote:

> Hello Gail and Hank,
> When I first started refiring some of my shinos in my electric kiln,
> I only fired them to bisque, and they were not successful. When
> touched they seemed to have a "skin" on them, and tiny, tiny, crazing
> all over. I did a few tests on going higher in temp. I ended up
> going to 1950F, and soaking for 2 hours before turning it off, with
> the top peep open. The shino was redder, more depth of color, and
> lustred where there was ugly carbon trapping.
> Meticky Liz from Grafton, Ontario, Canada

Hallelulia Liz;

What you report confirms what the draw trials told me about shinos. The
crystal development occurs around 1900F. Didn't know an electric could
do it though.

Cheers, Hank
www.murrow.biz/hank

John Hesselberth on tue 7 jun 05


On Jun 6, 2005, at 3:57 PM, Hank Murrow wrote:

> I have experienced several results similar to your description. My
> theory is that electric kilns fire neutral, not oxidizing.
> Shino-firecolor needs some oxidation to develop the reddish color of
> ferrite crystals, and most gas kilns can fire in oxidation.

Hi Hank,

I have a different theory. I don't believe oxidation vs. neutral=20
atmosphere has anything to do with it. Here is the theory I am working=20=

off of. Iron oxide has limited solubility in a silica melt and that=20
solubility drops as temperature drops. So when the glaze is fully=20
melted it can hold quite a bit of iron. The trick to developing iron=20
reds (or reddening up a glaze that has some iron in it at the=20
body/glaze interface) is to find the temperature for your particular=20
glaze where the glaze is still fluid enough to allow things to move=20
around, albeit slowly, but where the solubility of iron has dropped to=20=

the point where it wants to precipitate out as crystals. Then hold it=20
there for a couple hours so that can happen.

That is what Liz is apparently doing with her 1950 hold. For one of the=20=

cone 6 glazes I am working with it seems to occur at about 1600.

That's my 2=A2 worth--another theory to test.

Regards,

John

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

Lee Love on tue 7 jun 05


Hank Murrow wrote:

>
> Clayarter with positive ventilation in their electric could get an
> oxidizing atmosphere and confirm what is only a hunch on my part. Time
> at temperature, however, is always a factor as you suggest.

The big handicap of modern electric kilns is that they cool very fast.
Maybe cool down firing would make up for this in the bisque?

--
李 Lee Love 大
愛      鱗
in Mashiko, Japan http://mashiko.org
http://hankos.blogspot.com/ Visual Bookmarks
http://ikiru.blogspot.com/ Zen and Craft

"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)

Hank Murrow on tue 7 jun 05


On Jun 7, 2005, at 8:42 AM, John Hesselberth wrote:

> Hi Hank,
>
> I have a different theory. I don't believe oxidation vs. neutral=20
> atmosphere has anything to do with it. Here is the theory I am working=20=

> off of. Iron oxide has limited solubility in a silica melt and that=20
> solubility drops as temperature drops. So when the glaze is fully=20
> melted it can hold quite a bit of iron. The trick to developing iron=20=

> reds (or reddening up a glaze that has some iron in it at the=20
> body/glaze interface) is to find the temperature for your particular=20=

> glaze where the glaze is still fluid enough to allow things to move=20
> around, albeit slowly, but where the solubility of iron has dropped to=20=

> the point where it wants to precipitate out as crystals. Then hold it=20=

> there for a couple hours so that can happen. That is what Liz is=20
> apparently doing with her 1950 hold. For one of the cone 6 glazes I am=20=

> working with it seems to occur at about 1600. That's my 2=A2=20
> worth--another theory to test.

Dear John;

An excellent suggestion. As soon as I have access to a smaller gas=20
kiln(so as to minimize unpleasant surprises), I will try a cooling soak=20=

in reduction around 1900F to confirm your theory. I am not a betting=20
man, but my money is on oxidation in the cooling for Shinos.

Cheers, Hank
www.murrow.biz/hank

Craig Martell on tue 7 jun 05


John H. wrote:

>I have a different theory. I don't believe oxidation vs. neutral
>atmosphere has anything to do with it.

Hello John and Hank:

Sure it does. Your theory of movement of molecules as a function of time
and heatwork is correct from what we see in glazes and geologic
processess. But some of the iron will move to the surface of the glaze
where it can crystallize and also be affected by oxygen. You will usually
see some fire color in shinos that have only been thru a reduction
fire. Further exposure to oxygen with a second fire in an electric
enhances and intensifies the influcence of the oxygen. Crystals are
another product of time and heatwork at the temp we are talking
about. I've refired tenmokus and shinos at about 1988F and also
celadons. The shinos and tenmokus will develop a warm red but the celadons
stay green and crystallize more because of the amount of Fe and the glaze
composition.

regards, Craig Martell Hopewell, Oregon

Hank Murrow on wed 8 jun 05


On Jun 8, 2005, at 6:07 PM, Gail Dapogny wrote:

> Don't forget that many potters -- myself included -- are using
> Malcolm's shino which has redart in the glaze. Does this affect what
> any of you are saying about the presence of iron? Again, I'm not
> knowledgeable enough to be in on this discussion, but I did want to
> interject this fact.

Dear Gail;

Good Point! Hank here. All my remarks have been from my experience with
soda-ash-free Shinos. There are no materials in my glazes that have
significant amounts of iron. The glazes have tested out at around 1% to
1.5% iron. They are white, except where the red color has developed. I
do use a darkish body for most of this work.

Cheers, Hank
www.murrow.biz/hank

Hank Murrow on wed 8 jun 05


On Jun 8, 2005, at 8:23 PM, Tom at Hutchtel wrote:

> Has anyone taken a grinder and gone through the surface to see what's
> underneath? Might be a clue.
>
> We use Shaners oribe over a matte white. Sometimes when we've fired
> light
> reduction throughout, with some oxidation at the end, we get a green
> over
> white. Occasional red flash. But if you grind into the green areas,
> especially where thick, it's red underneath. And no, the green isn't
> brownish...it's the deep oribe green.

Dear Tom;

Most of my copper/Barium greens and blues are red underneath if I fired
them in a reduction fire. The red shinos are white underneath. Never
used the Oribe type.

Cheers, Hank
www.murrow.biz/hank

John Hesselberth on wed 8 jun 05


On Jun 7, 2005, at 6:44 PM, Craig Martell wrote:

> I've refired tenmokus and shinos at about 1988F and also
> celadons. The shinos and tenmokus will develop a warm red but the
> celadons
> stay green and crystallize more because of the amount of Fe and the
> glaze
> composition.

Hi Craig,

I'm trying to understand how much of the reducible materials--what
percentage--actually get reduced in a reduction firing. My current
hypothesis is that it is a fairly small percentage--enough to affect
the color, but nowhere near 100%. Again a hypothesis I would like to
see tested is that it is actually the unreduced residual iron that
results in the reddening on refiring because it crystallized out of
solution--not reduced iron that reoxidizes and then crystallizes.

I have no trouble accepting that in a tenmoku, where the iron is
throughout the glaze, that some surface reoxidation occurs in a
refiring. But in a shino where the iron is only in the body, I am
struggling to accept that that iron can migrate to the surface in a
refiring--or that oxygen can migrate through the nearly solid glaze and
reoxidize it in place.

A long background in heat, mass, and momentum transfer causes me to be
skeptical that these molecules move more than a few molecular diameters
in a refiring to only 1900-2000.

Regards,

John

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

Lee Love on wed 8 jun 05


John Hesselberth wrote:

>
> refiring. But in a shino where the iron is only in the body, I am
> struggling to accept that that iron can migrate to the surface in a
> refiring--or that oxygen can migrate through the nearly solid glaze and
> reoxidize it in place.

There are noticeable amounts of iron in the glaze materials of
traditional shinos. I have realized when converting to American
materials from Japanese, and you only use kaolin as the clay, you have
to add both alumina and iron. As little as .8% iron.

I thought Hank proved this:

http://www.ceramicsmonthly.org/mustreads/shinofire.asp

In 1994, I visited Pamela Vandiver at the Smithsonian Institution's
Conservation Laboratory, where she prepared samples of my Shinos for
electron microscope and X-ray diffraction analysis. We have yet to fully
understand the results, but we do know that the fire color is a layer of
ferric microcrystals, just 20 microns thick, floating on the white
glaze. Even the bloodiest Shinos were white just under the extremely
thin red layer, suggesting that severe abrasion in use should be
avoided; however, we have used red Shino plates at our table for 15
years without problems.

http://www.ceramicsmonthly.org/mustreads/shinofire.asp

> A long background in heat, mass, and momentum transfer causes me to be
> skeptical that these molecules move more than a few molecular diameters
> in a refiring to only 1900-2000.

That may be all you need. Actually, the molecules
may not have to move any appreciable distance but only realign the
crystal structure.

My experience (and Euan's too) leads me to believe that
alumina is very important for the red color, only requiring very small
amounts of iron in the glaze, especially in wood or soda "vapor" firing.

--
? Lee Love ?
? ?
in Mashiko, Japan http://mashiko.org
http://hankos.blogspot.com/ Visual Bookmarks
http://ikiru.blogspot.com/ Zen and Craft

"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)

Jim Murphy on wed 8 jun 05


Hi all,

For Shino's, I'm wondering what part Sulfur compounds in the body - along
with the redox ratio (FeO:Fe2O3) - may play in "color" formation.

Recent advanced glass-tint research suggests a higher redox ratio leads to
Amber (Reddish-Orange) coloration due to the formation of Iron Polysulfides.
[For those with access, see "Value-Added Flat-Glass Products, Part I",
Ceramics Bulletin, January 2005]

Granted, the research was done in Soda-Lime glass compositions, however,
it's "possible" a similar coloring mechanism may be at play in Shino's.

Sulfur compounds in a clay body are known to readily reduce Iron, i.e., more
FeO causing a higher FeO:Fe2O3 redox ratio possibly creating a more
Reddish-Orange color.

Is the formation of Iron Polysulfides the "ancient secret" ???

Just a thought.

Best wishes,

Jim Murphy

Hank Murrow on wed 8 jun 05


On Jun 8, 2005, at 7:19 AM, Lee Love wrote:

> My experience (and Euan's too) leads me to believe that
> alumina is very important for the red color, only requiring very small
> amounts of iron in the glaze, especially in wood or soda "vapor"
> firing.

Dear Lee;

The Si/Al ratio for Hank's Shino is 3.3/1
The Al2O3 is 1.59 moles! Way high. I suggest this confirms your
experience.

Cheers, Hank
www.murrow.biz/hank

Hank Murrow on wed 8 jun 05


On Jun 8, 2005, at 5:05 AM, John Hesselberth wrote, in part:
>
> I have no trouble accepting that in a tenmoku, where the iron is
> throughout the glaze, that some surface reoxidation occurs in a
> refiring. But in a shino where the iron is only in the body, I am
> struggling to accept that that iron can migrate to the surface in a
> refiring--or that oxygen can migrate through the nearly solid glaze and
> reoxidize it in place.

Dear John;

It takes only a miniscule amount of iron to form this indian red if the
glaz eis very high in Alumina. Mine has a Si/AL ratio of 3.3/1, which
iks very high in Alumina. Pamela Vandiver and I found NO increase in
iron anywhere between the clay-glaze interface and the surface. Yet,
the strong red color on the surface was undeniable, as was the very
white color throughout the glaze. See #082 on this page of my site:
http://www.murrow.biz/hank/shino-pots.htm for a good example.

4 hours of oxidation at 1900F during the cooling.
www.murrow.biz/hank

Craig Martell on wed 8 jun 05


John H. wrote:
>I have no trouble accepting that in a tenmoku, where the iron is
>throughout the glaze, that some surface reoxidation occurs in a
>refiring. But in a shino where the iron is only in the body, I am
>struggling to accept that that iron can migrate to the surface in a
>refiring--or that oxygen can migrate through the nearly solid glaze and
>reoxidize it in place.

Hello again John:

If we factor in the iron from ball clay content of a shino plus the small
amounts of iron supplied by kaolin and any of the other materials we have
to conclude that there's iron in the glaze too. Not just iron supplied
from the claybody.

Shinos are blended to inhibit iron from being taken into solution. You
will see in most shinos that calcium is very low and alumina is unusually
high. I don't think this is an accident. Calcium will take iron into
solution. So by reducing the CaO and upping the alumina we can allow small
amounts of iron to make the different shades of "fire color" in a
shino. The composition of a shino is so radical in this sense that these
minute amounts of iron produce color that we don't see in other types of glaze.

I've done several Currie biaxials of different shinos and have noticed the
same characteristics in all the tests regarding levels of alumina and fire
color. In one test I wanted to separate the effects of alumina and silica
so I added pure alumia oxide to the mix instead of using kaolin or ball
clay for the alumina. As the level of alumina increased against the fluxes
and silica, the glazes became redder. On the other side of the tile where
there was more silica the glazes were orange to orange/white. In the flux
corners and in the areas of low alumina the glazes were glassy celadons.

I think that reoxidation of reduced iron is the mechanism we are seeing
with the redder shino refires. It's like what we see in a reduced iron
bearing claybody with a clear glaze. Where the glaze inhibits reoxidation
of the claybody, we see a grey color while the unglazed clay is able to
reoxidize and we see warmer colors. The silica/alumina ratios of most
shinos,. coincidentally, are more like the ratios we see in claybodies.

If the reoxidation of reduced iron is not what is making the reds redder in
a refire, why couldn't we fire shinos in an electric kiln at varying
lengths of time and temp to produce these reds? I think, in the final
analysis, you'll find that the iron needs to be reduced and reoxidized to
produce this effect.

regards, Craig Martell Hopewell, Oregon

John Hesselberth on wed 8 jun 05


On Jun 8, 2005, at 1:22 PM, Hank Murrow wrote:

> Pamela Vandiver and I found NO increase in
> iron anywhere between the clay-glaze interface and the surface. Yet,
> the strong red color on the surface was undeniable, as was the very
> white color throughout the glaze. See #082 on this page of my site:

Hi Hank, Craig, Lee,

OK, I can buy into the fact that it is only surface iron that is
providing the color and that there may be enough as impurities in the
ingredients to provide that color and that high alumina is necessary.

But then wouldn't your shino recipes fired in strict oxidation from the
start also develop a red surface on refiring--or maybe just with a very
slow cooling in an oxidizing atmosphere? Said another way, what is it
about reduction first followed by a refiring in oxidizing atmosphere
that develops the red color where straight oxidizing/oxidizing firings
don't? Help me understand this.

John

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

Hank Murrow on wed 8 jun 05


Dear Shinoistes;

I concur with Craig's post here, because it conforms to what was
measured at the Smithsonian Conservation Lab and also my own 35 year
experience, at least with my soda-ash-free shinos which are loaded with
Al2O3. At the Lab, Pamela and I found iron under 2% throughout the
glaze thickness with less than 0.2% variation. All samples were reddish
at the surface and white underneath, all the way to the glaze/clay
interface. The color was measured at approx(+/- 5 microns0 at 20
microns. Thbat is really thin.

Bravo, Craig

Hank in Eugene

On Jun 8, 2005, at 12:24 PM, Craig Martell wrote:
>
> If we factor in the iron from ball clay content of a shino plus the
> small
> amounts of iron supplied by kaolin and any of the other materials we
> have
> to conclude that there's iron in the glaze too. Not just iron supplied
> from the claybody.
>
> Shinos are blended to inhibit iron from being taken into solution. You
> will see in most shinos that calcium is very low and alumina is
> unusually
> high. I don't think this is an accident. Calcium will take iron into
> solution. So by reducing the CaO and upping the alumina we can allow
> small
> amounts of iron to make the different shades of "fire color" in a
> shino. The composition of a shino is so radical in this sense that
> these
> minute amounts of iron produce color that we don't see in other types
> of glaze.
>
> I've done several Currie biaxials of different shinos and have noticed
> the
> same characteristics in all the tests regarding levels of alumina and
> fire
> color. In one test I wanted to separate the effects of alumina and
> silica
> so I added pure alumia oxide to the mix instead of using kaolin or ball
> clay for the alumina. As the level of alumina increased against the
> fluxes
> and silica, the glazes became redder. On the other side of the tile
> where
> there was more silica the glazes were orange to orange/white. In the
> flux
> corners and in the areas of low alumina the glazes were glassy
> celadons.
>
> I think that reoxidation of reduced iron is the mechanism we are seeing
> with the redder shino refires. It's like what we see in a reduced iron
> bearing claybody with a clear glaze. Where the glaze inhibits
> reoxidation
> of the claybody, we see a grey color while the unglazed clay is able to
> reoxidize and we see warmer colors. The silica/alumina ratios of most
> shinos,. coincidentally, are more like the ratios we see in claybodies.
>
> If the reoxidation of reduced iron is not what is making the reds
> redder in
> a refire, why couldn't we fire shinos in an electric kiln at varying
> lengths of time and temp to produce these reds? I think, in the final
> analysis, you'll find that the iron needs to be reduced and reoxidized
> to
> produce this effect.
>
> regards, Craig Martell Hopewell, Oregon
>
> _______________________________________________________________________
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>
>
www.murrow.biz/hank

Hank Murrow on wed 8 jun 05


On Jun 8, 2005, at 12:39 PM, John Hesselberth wrote:
>
> Hi Hank, Craig, Lee,
>
> OK, I can buy into the fact that it is only surface iron that is
> providing the color and that there may be enough as impurities in the
> ingredients to provide that color and that high alumina is necessary.
>
> But then wouldn't your shino recipes fired in strict oxidation from the
> start also develop a red surface on refiring--or maybe just with a very
> slow cooling in an oxidizing atmosphere? Said another way, what is it
> about reduction first followed by a refiring in oxidizing atmosphere
> that develops the red color where straight oxidizing/oxidizing firings
> don't? Help me understand this.

Dear John;

I am just as mystified as you are. My experience with these high
Alumina shinos is that if you miss the early reduction you won't get
color no matter how it is fired subsequently. My theory, and it is just
that........uncorroborated), is that reduction is necessary to get the
iron into solution at the surface, where it can later be oxidized to
the red color.

My nickle's worth,

Hank
www.murrow.biz/hank

Gail Dapogny on wed 8 jun 05


Don't forget that many potters -- myself included -- are using
Malcolm's shino which has redart in the glaze. Does this affect what
any of you are saying about the presence of iron? Again, I'm not
knowledgeable enough to be in on this discussion, but I did want to
interject this fact.
Otherwise, I'm all ears (so to speak): i.e. struggling a lot to
understand what you are all saying, but most appreciative of the
dialogue, and saving every word.
Gail in Ann Arbor

On Jun 8, 2005, at 3:24 PM, Craig Martell wrote:

> John H. wrote:
>> I have no trouble accepting that in a tenmoku, where the iron is
>> throughout the glaze, that some surface reoxidation occurs in a
>> refiring. But in a shino where the iron is only in the body, I am
>> struggling to accept that that iron can migrate to the surface in a
>> refiring--or that oxygen can migrate through the nearly solid glaze
>> and
>> reoxidize it in place.
>
> Hello again John:
>
> If we factor in the iron from ball clay content of a shino plus the
> small
> amounts of iron supplied by kaolin and any of the other materials we
> have
> to conclude that there's iron in the glaze too. Not just iron supplied
> from the claybody.
>

Tom at Hutchtel on wed 8 jun 05


Has anyone taken a grinder and gone through the surface to see what's
underneath? Might be a clue.

We use Shaners oribe over a matte white. Sometimes when we've fired light
reduction throughout, with some oxidation at the end, we get a green over
white. Occasional red flash. But if you grind into the green areas,
especially where thick, it's red underneath. And no, the green isn't
brownish...it's the deep oribe green.

Get out those grinders.

Tom
----- Original Message -----
From: "John Hesselberth"
> Hi Hank, Craig, Lee,
>
> OK, I can buy into the fact that it is only surface iron that is
> providing the color and that there may be enough as impurities in the
> ingredients to provide that color and that high alumina is necessary.
>
> But then wouldn't your shino recipes fired in strict oxidation from the
> start also develop a red surface on refiring--or maybe just with a very
> slow cooling in an oxidizing atmosphere? Said another way, what is it
> about reduction first followed by a refiring in oxidizing atmosphere
> that develops the red color where straight oxidizing/oxidizing firings
> don't? Help me understand this.

Hank Murrow on thu 9 jun 05


On Jun 9, 2005, at 7:17 AM, Ben wrote:

> Why is the soak at 1900?
> What happens if it gets hotter?
>
> I fired down last night. Had let it cool to 1775 as I was searching
> the
> archives to see if I would blow the carbon trapping. Dannon said no.
> Liz said you lose a little.
> So I fired back up kinda quick to 1900, sat 15 min with no change went
> to bed for an hour and a half. Got up at 2am to shut it down it had
> crept up to 2000. It's down to 1400 and with a light I can see there
> is
> still some carbon. Still wondering about color. Oh the wait...

Dear Ben;

I have had many 'wait' times, hoping for something good...... or at
least clarifying. I wish you luck, but more I wish you clarity. may
take a couple more fires with better planning to see the results with
that clarity. I recommend strongly that you make up some draw trials
while you are in wait mode......... at least ten little rings with some
texture. Dip each in your shino and start pulling one every hour once
the fire is complete. They will tell you most of what you want to know.

Cheers, and looking for the report here......

Hank
www.murrow.biz/hank

Ben on thu 9 jun 05


Why is the soak at 1900?
What happens if it gets hotter?

I fired down last night. Had let it cool to 1775 as I was searching the
archives to see if I would blow the carbon trapping. Dannon said no.
Liz said you lose a little.
So I fired back up kinda quick to 1900, sat 15 min with no change went
to bed for an hour and a half. Got up at 2am to shut it down it had
crept up to 2000. It's down to 1400 and with a light I can see there is
still some carbon. Still wondering about color. Oh the wait...
Take care,
Ben