gary navarre on thu 5 aug 10
Hey Folks,
A long time ago I read Hamada bought up some Pine forests and had a thing =
about using 30 year old Red Pines so I thought that's what was the best to =
use. Eventually I came into 10 acres of mixed pines and had a ball trimming=
out dead limbs and sticks for kiln fuel. Over the years I of course learne=
d to accept there are many brands of woods and plants that can get clay hot=
, some better and hotter than others, and Red Pine is not necessarily the b=
est. The split slabs I used smoked like Russia burning. Still I thought abo=
ut why Hamada would be so specific until I cut down a tall dead Spruce abou=
t 5" or so at the base and counted the growth rings. The tree was about 30 =
years old. I was looking for stoking sticks 5" around and under because any=
bigger became to big to conveniently stoke in the Bourry. That's when I re=
alized an older tree would be bigger and then need splitting. My main stoke=
holes can take up to 10"x16" chunks in the Pig-nose and the Bourry
box gets up to 5"x32"-35.5". Any bigger is to heavy to stoke and gives the=
walls a real beating. Once a tree gets over 6" at the base one might as we=
ll let it grow more and keep it trimmed to make clear lumber.
I also learned most loggers haven't thought that way for a long time and c=
lear cut with processors. They have left us with a bunch of Maple, Poplar, =
Ash, Ironwood, Balsam, and Spruce sticks under 6" around. Also just before =
Christmas season we cut Balsam, Spruce, White Pine, and Cedar for decoratio=
ns so I have available more than the old single species I thought I had to =
use because that's what Hamada used and he made great pots. Hamada made gre=
at pots because he was Hamada not because he used 30 year old Red Pine. He =
and his firemen just didn't want to stoke anything heavier or split huge lo=
gs.
So I what I'm wondering is with these woods available in what ways or in w=
hat order would you solid fuel fanatics use these different woods in the di=
fferent stages of a 3 day or longer firing? I finally got to read Dick Lehm=
ans description of arriving at a longer stoking pattern similar to what I w=
as thinking in the mid '80's, although I was keeping the firebox smaller, w=
ith similar advantages of letting the kiln fire unattended. At some stage w=
e just want to make a dry heat, some to build up ash and keep the heat even=
, then some to get the temperature to climb, some to blast the load to melt=
the ash and glaze, some stoke to soak and/or side stoke. After making some=
adjustment repairs on the Pig-nose and Bourry box to get better control of=
my coal pile at the throat arch with more air through the mouse-hole...
http://public.fotki.com/GindaUP/ca/kpap/uphwfkl3/bourry-box-mousehol.html
... I think I might be able to use some percentage of hardwood to keep a st=
eady high heat with a good coal pile and still have room above the throat a=
rch for the skinny sticks to give off their fast burn and make the temperat=
ure rise...
http://public.fotki.com/GindaUP/ca/kpap/uphwfkl3/hob-6in-wider-jpg.html
When those are spent the big stuff above the coal pile will hold the sligh=
t rise until the next blasting stoke of skinny stuff. I used a similar patt=
ern at the end of firing my smaller Hobagama and the big stuff was all pine=
but it lasted enough to do the trick. For some reason side stoking did not=
drag ash through the front settings and most glazes were smooth and shiny.=
Maybe I can find some old kiln logs and see if they say what I might have =
done. I might have pasted the primary and secondary air closed.
There is other tweaking I can do to the kiln later but I wanted to see wha=
t others experience has been with different wood fuels and share it just in=
case some newcomers haven't seen previous discussions and I might have som=
ething new to think about so thanks and stay in there eh.
Gary Navarre
Navarre Pottery
Navarre Enterprises
Norway, Michigan, USA
http://www.youtube.com/GindaUP
http://public.fotki.com/GindaUP/
tony clennell on thu 5 aug 10
Gary: Red pine is a smoker. I can't use it where I live as my wood
kiln would be shut down in a heart beat. There is an invaluable chart
at the back of Jack Troy's book on Wood firing that lists the
different species of wood and their characteristics as to coaling,
smoke, btu's, weight, splitability. My last firing we used red oak and
it was a bugger with not such a pretty ash. Kinda dirty green.
If you are having coaling problems is there a way you could introduce
a step grate over that mousehole of yours? The step grate is a good
way of burning the coals down and the wood lands on the step and not
flat on top of itself which increases the surface area of the wood
burning.
My favourite wood of all time was hickory. It burned hotter than a
southern girl on prom night and had a lovely perfume to boot.
Glad I'm not wood firing in this heat. I haven't had a good nights
sleep in weeks.
Cheers,
Tony
On Thu, Aug 5, 2010 at 5:45 AM, gary navarre
wrote:
> Hey Folks,
>
> =3DA0A long time ago I read Hamada bought up some Pine forests and had a =
th=3D
ing about using 30 year old Red Pines so I thought that's what was the best=
=3D
to use. Eventually I came into 10 acres of mixed pines and had a ball trim=
=3D
ming out dead limbs and sticks for kiln fuel. Over the years I of course le=
=3D
arned to accept there are many brands of woods and plants that can get clay=
=3D
hot, some better and hotter than others, and Red Pine is not necessarily t=
=3D
he best. The split slabs I used smoked like Russia burning. Still I thought=
=3D
about why Hamada would be so specific until I cut down a tall dead Spruce =
=3D
about 5" or so at the base and counted the growth rings. The tree was about=
=3D
30 years old. I was looking for stoking sticks 5" around and under because=
=3D
any bigger became to big to conveniently stoke in the Bourry. That's when =
=3D
I realized an older tree would be bigger and then need splitting. My main s=
=3D
toke holes can take up to 10"x16" chunks in the Pig-nose and the Bourry
> =3DA0box gets up to 5"x32"-35.5". Any bigger is to heavy to stoke and giv=
es=3D
the walls a real beating. Once a tree gets over 6" at the base one might a=
=3D
s well let it grow more and keep it trimmed to make clear lumber.
>
> =3DA0I also learned most loggers haven't thought that way for a long time=
a=3D
nd clear cut with processors. They have left us with a bunch of Maple, Popl=
=3D
ar, Ash, Ironwood, Balsam, and Spruce sticks under 6" around. Also just bef=
=3D
ore Christmas season we cut Balsam, Spruce, White Pine, and Cedar for decor=
=3D
ations so I have available more than the old single species I thought I had=
=3D
to use because that's what Hamada used and he made great pots. Hamada made=
=3D
great pots because he was Hamada not because he used 30 year old Red Pine.=
=3D
He and his firemen just didn't want to stoke anything heavier or split hug=
=3D
e logs.
>
> =3DA0So I what I'm wondering is with these woods available in what ways o=
r =3D
in what order would you solid fuel fanatics use these different woods in th=
=3D
e different stages of a 3 day or longer firing? I finally got to read Dick =
=3D
Lehmans description of arriving at a longer stoking pattern similar to what=
=3D
I was thinking in the mid '80's, although I was keeping the firebox smalle=
=3D
r, with similar advantages of letting the kiln fire unattended. At some sta=
=3D
ge we just want to make a dry heat, some to build up ash and keep the heat =
=3D
even, then some to get the temperature to climb, some to blast the load to =
=3D
melt the ash and glaze, some stoke to soak and/or side stoke. After making =
=3D
some adjustment repairs on the Pig-nose and Bourry box to get better contro=
=3D
l of my coal pile at the throat arch with more air through the mouse-hole..=
=3D
.
>
> http://public.fotki.com/GindaUP/ca/kpap/uphwfkl3/bourry-box-mousehol.html
>
> ... I think I might be able to use some percentage of hardwood to keep a =
=3D
steady high heat with a good coal pile and still have room above the throat=
=3D
arch for the skinny sticks to give off their fast burn and make the temper=
=3D
ature rise...
>
> http://public.fotki.com/GindaUP/ca/kpap/uphwfkl3/hob-6in-wider-jpg.html
>
> =3DA0When those are spent the big stuff above the coal pile will hold the=
s=3D
light rise until the next blasting stoke of skinny stuff. I used a similar =
=3D
pattern at the end of firing my smaller Hobagama and the big stuff was all =
=3D
pine but it lasted enough to do the trick. For some reason side stoking did=
=3D
not drag ash through the front settings and most glazes were smooth and sh=
=3D
iny. Maybe I can find some old kiln logs and see if they say what I might h=
=3D
ave done. I might have pasted the primary and secondary air closed.
>
> =3DA0There is other tweaking I can do to the kiln later but I wanted to s=
ee=3D
what others experience has been with different wood fuels and share it jus=
=3D
t in case some newcomers haven't seen previous discussions and I might have=
=3D
something new to think about so thanks and stay in there eh.
>
> Gary Navarre
> Navarre Pottery
> Navarre Enterprises
> Norway, Michigan, USA
> http://www.youtube.com/GindaUP
> http://public.fotki.com/GindaUP/
>
Eva Gallagher on thu 5 aug 10
Hi Gary,
I did a test once of just different ash samples to see how they melted. It
was just fired to cone 8 in an electric so not really indicative as none
really melted. The one that looked the best (not totally dry) was red pine
and white pine as they also gave some color flashing around the edges vs
oak, butternut, ironwood, ash which were totally dry and no color. I think
birch was not too bad either. The BBQ ash was the only one that did seem to
melt somewhat - so obviously some additive there.
Am planning to do my second wood firing in 3 years but this time I have
lined up some white pine to go along with the ironwood. Using ironwood last
time I just had too much coal build up. Pine is also supposed to have a
really long flame so that should help even out the heat. I am also going to
brush some soda ash on some of the pots to get some fluxing in the dry area=
s
as Lee has suggested.
Really enjoying following your wood firing journey.
Eva Gallagher
Deep River, Ontario
http://newfoundoutpotter.blogspot.com/
http://www.valleyartisans.com/gallagher/Gallagher.htm
----- Original Message -----
From: "gary navarre"
To:
Sent: Thursday, August 05, 2010 5:45 AM
Subject: 30 Year Old Red Pine or Multi-wood firings, why & how?
> Hey Folks,
>
> A long time ago I read Hamada bought up some Pine forests and had a thing
> about using 30 year old Red Pines so I thought that's what was the best t=
o
> use. Eventually I came into 10 acres of mixed pines and had a ball
> trimming out dead limbs and sticks for kiln fuel. Over the years I of
> course learned to accept there are many brands of woods and plants that
> can get clay hot, some better and hotter than others, and Red Pine is not
> necessarily the best. The split slabs I used smoked like Russia burning.
> Still I thought about why Hamada would be so specific until I cut down a
> tall dead Spruce about 5" or so at the base and counted the growth rings.
> The tree was about 30 years old. I was looking for stoking sticks 5"
> around and under because any bigger became to big to conveniently stoke i=
n
> the Bourry. That's when I realized an older tree would be bigger and then
> need splitting. My main stoke holes can take up to 10"x16" chunks in the
> Pig-nose and the Bourry
> box gets up to 5"x32"-35.5". Any bigger is to heavy to stoke and gives th=
e
> walls a real beating. Once a tree gets over 6" at the base one might as
> well let it grow more and keep it trimmed to make clear lumber.
>
> I also learned most loggers haven't thought that way for a long time and
> clear cut with processors. They have left us with a bunch of Maple,
> Poplar, Ash, Ironwood, Balsam, and Spruce sticks under 6" around. Also
> just before Christmas season we cut Balsam, Spruce, White Pine, and Cedar
> for decorations so I have available more than the old single species I
> thought I had to use because that's what Hamada used and he made great
> pots. Hamada made great pots because he was Hamada not because he used 30
> year old Red Pine. He and his firemen just didn't want to stoke anything
> heavier or split huge logs.
>
> So I what I'm wondering is with these woods available in what ways or in
> what order would you solid fuel fanatics use these different woods in the
> different stages of a 3 day or longer firing? I finally got to read Dick
> Lehmans description of arriving at a longer stoking pattern similar to
> what I was thinking in the mid '80's, although I was keeping the firebox
> smaller, with similar advantages of letting the kiln fire unattended. At
> some stage we just want to make a dry heat, some to build up ash and keep
> the heat even, then some to get the temperature to climb, some to blast
> the load to melt the ash and glaze, some stoke to soak and/or side stoke.
> After making some adjustment repairs on the Pig-nose and Bourry box to ge=
t
> better control of my coal pile at the throat arch with more air through
> the mouse-hole...
>
> http://public.fotki.com/GindaUP/ca/kpap/uphwfkl3/bourry-box-mousehol.html
>
> ... I think I might be able to use some percentage of hardwood to keep a
> steady high heat with a good coal pile and still have room above the
> throat arch for the skinny sticks to give off their fast burn and make th=
e
> temperature rise...
>
> http://public.fotki.com/GindaUP/ca/kpap/uphwfkl3/hob-6in-wider-jpg.html
>
> When those are spent the big stuff above the coal pile will hold the
> slight rise until the next blasting stoke of skinny stuff. I used a
> similar pattern at the end of firing my smaller Hobagama and the big stuf=
f
> was all pine but it lasted enough to do the trick. For some reason side
> stoking did not drag ash through the front settings and most glazes were
> smooth and shiny. Maybe I can find some old kiln logs and see if they say
> what I might have done. I might have pasted the primary and secondary air
> closed.
>
> There is other tweaking I can do to the kiln later but I wanted to see
> what others experience has been with different wood fuels and share it
> just in case some newcomers haven't seen previous discussions and I might
> have something new to think about so thanks and stay in there eh.
>
> Gary Navarre
> Navarre Pottery
> Navarre Enterprises
> Norway, Michigan, USA
> http://www.youtube.com/GindaUP
> http://public.fotki.com/GindaUP/
>
>
James Freeman on thu 5 aug 10
Gary...
At the local college, we fire almost entirely with scrap wood from a
hardwood flooring plant. It is mostly red oak, probably 95%, but
there is also a smattering of maple, hickory, walnut, and cherry.
We gain temperature quite readily, except for two sticking points at
1400 degrees F and 2100 degrees F (probably a flaw in the kiln
design). The young man I ordinarily wood fire with used to work
summers at a shop that made fake antique tables and benches for
fixtures in a chain of stores selling over-priced clothing to trendy
teenagers. The fixtures were made from salvaged cedar barn wood, and
he would bring trailer loads to the kiln. We used this very dry cedar
as "rocket fuel" to get us past the sticking points.
We got what I would consider to be good to very good ash buildup,
except for the top shelf which is out of the direct draft from the
firebox (a design flaw in the kiln, though it ends up being a good
place for glazed work). The melted ash tends toward a soft, matte to
semi-matte, grey to white-ish. There are a few such pots on my flickr
page, bottom of page 4 and top of page 5. So, that's my experience
with oak.
Dick Lehman told me that he did an entire firing with cherry, and that
it was the worst firing of his life. He said that the cherry produced
almost no ash, nor flashing, nor much else beside heat.
That's all the input I can give you, my friend. I hope it helps some.
All the best.
...James
James Freeman
"All I say is by way of discourse, and nothing by way of advice.=3DA0 I
should not speak so boldly if it were my due to be believed."
-Michel de Montaigne
http://www.jamesfreemanstudio.com
http://www.flickr.com/photos/jamesfreemanstudio/
http://www.jamesfreemanstudio.com/resources
On Thu, Aug 5, 2010 at 5:45 AM, gary navarre
wrote:
> Hey Folks,
>
> =3DA0A long time ago I read Hamada bought up some Pine forests and had a =
th=3D
ing about using 30 year old Red Pines so I thought that's what was the best=
=3D
to use. Eventually I came into 10 acres of mixed pines and had a ball trim=
=3D
ming out dead limbs and sticks for kiln fuel. Over the years I of course le=
=3D
arned to accept there are many brands of woods and plants that can get clay=
=3D
hot, some better and hotter than others, and Red Pine is not necessarily t=
=3D
he best. The split slabs I used smoked like Russia burning. Still I thought=
=3D
about why Hamada would be so specific until I cut down a tall dead Spruce =
=3D
about 5" or so at the base and counted the growth rings. The tree was about=
=3D
30 years old. I was looking for stoking sticks 5" around and under because=
=3D
any bigger became to big to conveniently stoke in the Bourry. That's when =
=3D
I realized an older tree would be bigger and then need splitting. My main s=
=3D
toke holes can take up to 10"x16" chunks in the Pig-nose and the Bourry
> =3DA0box gets up to 5"x32"-35.5". Any bigger is to heavy to stoke and giv=
es=3D
the walls a real beating. Once a tree gets over 6" at the base one might a=
=3D
s well let it grow more and keep it trimmed to make clear lumber.
>
> =3DA0I also learned most loggers haven't thought that way for a long time=
a=3D
nd clear cut with processors. They have left us with a bunch of Maple, Popl=
=3D
ar, Ash, Ironwood, Balsam, and Spruce sticks under 6" around. Also just bef=
=3D
ore Christmas season we cut Balsam, Spruce, White Pine, and Cedar for decor=
=3D
ations so I have available more than the old single species I thought I had=
=3D
to use because that's what Hamada used and he made great pots. Hamada made=
=3D
great pots because he was Hamada not because he used 30 year old Red Pine.=
=3D
He and his firemen just didn't want to stoke anything heavier or split hug=
=3D
e logs.
>
> =3DA0So I what I'm wondering is with these woods available in what ways o=
r =3D
in what order would you solid fuel fanatics use these different woods in th=
=3D
e different stages of a 3 day or longer firing? I finally got to read Dick =
=3D
Lehmans description of arriving at a longer stoking pattern similar to what=
=3D
I was thinking in the mid '80's, although I was keeping the firebox smalle=
=3D
r, with similar advantages of letting the kiln fire unattended. At some sta=
=3D
ge we just want to make a dry heat, some to build up ash and keep the heat =
=3D
even, then some to get the temperature to climb, some to blast the load to =
=3D
melt the ash and glaze, some stoke to soak and/or side stoke. After making =
=3D
some adjustment repairs on the Pig-nose and Bourry box to get better contro=
=3D
l of my coal pile at the throat arch with more air through the mouse-hole..=
=3D
.
>
> http://public.fotki.com/GindaUP/ca/kpap/uphwfkl3/bourry-box-mousehol.html
>
> ... I think I might be able to use some percentage of hardwood to keep a =
=3D
steady high heat with a good coal pile and still have room above the throat=
=3D
arch for the skinny sticks to give off their fast burn and make the temper=
=3D
ature rise...
>
> http://public.fotki.com/GindaUP/ca/kpap/uphwfkl3/hob-6in-wider-jpg.html
>
> =3DA0When those are spent the big stuff above the coal pile will hold the=
s=3D
light rise until the next blasting stoke of skinny stuff. I used a similar =
=3D
pattern at the end of firing my smaller Hobagama and the big stuff was all =
=3D
pine but it lasted enough to do the trick. For some reason side stoking did=
=3D
not drag ash through the front settings and most glazes were smooth and sh=
=3D
iny. Maybe I can find some old kiln logs and see if they say what I might h=
=3D
ave done. I might have pasted the primary and secondary air closed.
>
> =3DA0There is other tweaking I can do to the kiln later but I wanted to s=
ee=3D
what others experience has been with different wood fuels and share it jus=
=3D
t in case some newcomers haven't seen previous discussions and I might have=
=3D
something new to think about so thanks and stay in there eh.
>
> Gary Navarre
> Navarre Pottery
> Navarre Enterprises
> Norway, Michigan, USA
> http://www.youtube.com/GindaUP
> http://public.fotki.com/GindaUP/
>
Steve Mills on thu 5 aug 10
Interesting stuff this.
My Mentor Yves Crespel who potted in Brittany, France, used to fire to
1100oC with Pine, then from 1100 to 1200 with seasoned Oak, followed by the=
n
slats of Pine with the bark removed (he swore the bark took heat out of the
firebox).
He reckoned the Oak put real heat into the heart of the Kiln at the point
when it was most needed.
For myself, like James, I use scrap wood that normally goes into Landfill
(which I think is a shocking waste), mostly pine and the like and it's free=
.
With that I get pretty much the results that I want, the only bugger is
raking out the semi-welded nails from the bottom of the firebox when it's
all finished.
Steve Mills
On 5 August 2010 18:08, James Freeman wrote:
> Gary...
>
> At the local college, we fire almost entirely with scrap wood from a
> hardwood flooring plant. It is mostly red oak, probably 95%, but
> there is also a smattering of maple, hickory, walnut, and cherry.
>
> We gain temperature quite readily, except for two sticking points at
> 1400 degrees F and 2100 degrees F (probably a flaw in the kiln
> design). The young man I ordinarily wood fire with used to work
> summers at a shop that made fake antique tables and benches for
> fixtures in a chain of stores selling over-priced clothing to trendy
> teenagers. The fixtures were made from salvaged cedar barn wood, and
> he would bring trailer loads to the kiln. We used this very dry cedar
> as "rocket fuel" to get us past the sticking points.
>
> We got what I would consider to be good to very good ash buildup,
> except for the top shelf which is out of the direct draft from the
> firebox (a design flaw in the kiln, though it ends up being a good
> place for glazed work). The melted ash tends toward a soft, matte to
> semi-matte, grey to white-ish. There are a few such pots on my flickr
> page, bottom of page 4 and top of page 5. So, that's my experience
> with oak.
>
> Dick Lehman told me that he did an entire firing with cherry, and that
> it was the worst firing of his life. He said that the cherry produced
> almost no ash, nor flashing, nor much else beside heat.
>
> That's all the input I can give you, my friend. I hope it helps some.
>
> All the best.
>
> ...James
>
> James Freeman
>
> "All I say is by way of discourse, and nothing by way of advice. I
> should not speak so boldly if it were my due to be believed."
> -Michel de Montaigne
>
> http://www.jamesfreemanstudio.com
> http://www.flickr.com/photos/jamesfreemanstudio/
> http://www.jamesfreemanstudio.com/resources
>
>
>
>
> On Thu, Aug 5, 2010 at 5:45 AM, gary navarre
> wrote:
> > Hey Folks,
> >
> > A long time ago I read Hamada bought up some Pine forests and had a
> thing about using 30 year old Red Pines so I thought that's what was the
> best to use. Eventually I came into 10 acres of mixed pines and had a bal=
l
> trimming out dead limbs and sticks for kiln fuel. Over the years I of cou=
rse
> learned to accept there are many brands of woods and plants that can get
> clay hot, some better and hotter than others, and Red Pine is not
> necessarily the best. The split slabs I used smoked like Russia burning.
> Still I thought about why Hamada would be so specific until I cut down a
> tall dead Spruce about 5" or so at the base and counted the growth rings.
> The tree was about 30 years old. I was looking for stoking sticks 5" arou=
nd
> and under because any bigger became to big to conveniently stoke in the
> Bourry. That's when I realized an older tree would be bigger and then nee=
d
> splitting. My main stoke holes can take up to 10"x16" chunks in the Pig-n=
ose
> and the Bourry
> > box gets up to 5"x32"-35.5". Any bigger is to heavy to stoke and gives
> the walls a real beating. Once a tree gets over 6" at the base one might =
as
> well let it grow more and keep it trimmed to make clear lumber.
> >
> > I also learned most loggers haven't thought that way for a long time a=
nd
> clear cut with processors. They have left us with a bunch of Maple, Popla=
r,
> Ash, Ironwood, Balsam, and Spruce sticks under 6" around. Also just befor=
e
> Christmas season we cut Balsam, Spruce, White Pine, and Cedar for
> decorations so I have available more than the old single species I though=
t I
> had to use because that's what Hamada used and he made great pots. Hamada
> made great pots because he was Hamada not because he used 30 year old Red
> Pine. He and his firemen just didn't want to stoke anything heavier or sp=
lit
> huge logs.
> >
> > So I what I'm wondering is with these woods available in what ways or =
in
> what order would you solid fuel fanatics use these different woods in the
> different stages of a 3 day or longer firing? I finally got to read Dick
> Lehmans description of arriving at a longer stoking pattern similar to wh=
at
> I was thinking in the mid '80's, although I was keeping the firebox small=
er,
> with similar advantages of letting the kiln fire unattended. At some stag=
e
> we just want to make a dry heat, some to build up ash and keep the heat
> even, then some to get the temperature to climb, some to blast the load t=
o
> melt the ash and glaze, some stoke to soak and/or side stoke. After makin=
g
> some adjustment repairs on the Pig-nose and Bourry box to get better cont=
rol
> of my coal pile at the throat arch with more air through the mouse-hole..=
.
> >
> >
> http://public.fotki.com/GindaUP/ca/kpap/uphwfkl3/bourry-box-mousehol.html
> >
> > ... I think I might be able to use some percentage of hardwood to keep =
a
> steady high heat with a good coal pile and still have room above the thro=
at
> arch for the skinny sticks to give off their fast burn and make the
> temperature rise...
> >
> > http://public.fotki.com/GindaUP/ca/kpap/uphwfkl3/hob-6in-wider-jpg.html
> >
> > When those are spent the big stuff above the coal pile will hold the
> slight rise until the next blasting stoke of skinny stuff. I used a simil=
ar
> pattern at the end of firing my smaller Hobagama and the big stuff was al=
l
> pine but it lasted enough to do the trick. For some reason side stoking d=
id
> not drag ash through the front settings and most glazes were smooth and
> shiny. Maybe I can find some old kiln logs and see if they say what I mig=
ht
> have done. I might have pasted the primary and secondary air closed.
> >
> > There is other tweaking I can do to the kiln later but I wanted to see
> what others experience has been with different wood fuels and share it ju=
st
> in case some newcomers haven't seen previous discussions and I might have
> something new to think about so thanks and stay in there eh.
> >
> > Gary Navarre
> > Navarre Pottery
> > Navarre Enterprises
> > Norway, Michigan, USA
> > http://www.youtube.com/GindaUP
> > http://public.fotki.com/GindaUP/
> >
>
--
Steve
Bath
UK
www.mudslinger.me.uk
Growing old is inevitable, growing up is optional!
tony clennell on thu 5 aug 10
James wrote:
We gain temperature quite readily, except for two sticking points at
> 1400 degrees F and 2100 degrees F (probably a flaw in the kiln
> design).
James: I don't think it is necessarily a design flaw. Every wood kiln
I have fired has stalled around the two temperatures you mention. I
call this the time to burp or fart the kiln period. As I understand it
for every 690F that the temperature in the kiln rises the volume of
gases doubles. So with that in mind you can see 1400 and 2100 F are
critical times in the firing cycle. This usually has me putting in
less wood more often to get it to move this gas thru it's bowels so it
can eat some more. Especially the stall at 2100 when I get thru that
the kiln is hot to trot and I can go back to a normal charge of wood
in the firebox.
Bon feu!
Tony
On Thu, Aug 5, 2010 at 1:08 PM, James Freeman
wrote:
> Gary...
>
> At the local college, we fire almost entirely with scrap wood from a
> hardwood flooring plant. =3DA0It is mostly red oak, probably 95%, but
> there is also a smattering of maple, hickory, walnut, and cherry.
>
> =3DA0The young man I ordinarily wood fire with used to work
> summers at a shop that made fake antique tables and benches for
> fixtures in a chain of stores selling over-priced clothing to trendy
> teenagers. =3DA0The fixtures were made from salvaged cedar barn wood, and
> he would bring trailer loads to the kiln. =3DA0We used this very dry ceda=
r
> as "rocket fuel" to get us past the sticking points.
>
> We got what I would consider to be good to very good ash buildup,
> except for the top shelf which is out of the direct draft from the
> firebox (a design flaw in the kiln, though it ends up being a good
> place for glazed work). =3DA0The melted ash tends toward a soft, matte to
> semi-matte, grey to white-ish. =3DA0There are a few such pots on my flick=
r
> page, bottom of page 4 and top of page 5. =3DA0So, that's my experience
> with oak.
>
> Dick Lehman told me that he did an entire firing with cherry, and that
> it was the worst firing of his life. =3DA0He said that the cherry produce=
d
> almost no ash, nor flashing, nor much else beside heat.
>
> That's all the input I can give you, my friend. =3DA0I hope it helps some=
.
>
> All the best.
>
> ...James
>
> James Freeman
>
> "All I say is by way of discourse, and nothing by way of advice.=3DA0 I
> should not speak so boldly if it were my due to be believed."
> -Michel de Montaigne
>
> http://www.jamesfreemanstudio.com
> http://www.flickr.com/photos/jamesfreemanstudio/
> http://www.jamesfreemanstudio.com/resources
>
>
>
>
> On Thu, Aug 5, 2010 at 5:45 AM, gary navarre
> wrote:
>> Hey Folks,
>>
>> =3DA0A long time ago I read Hamada bought up some Pine forests and had a=
t=3D
hing about using 30 year old Red Pines so I thought that's what was the bes=
=3D
t to use. Eventually I came into 10 acres of mixed pines and had a ball tri=
=3D
mming out dead limbs and sticks for kiln fuel. Over the years I of course l=
=3D
earned to accept there are many brands of woods and plants that can get cla=
=3D
y hot, some better and hotter than others, and Red Pine is not necessarily =
=3D
the best. The split slabs I used smoked like Russia burning. Still I though=
=3D
t about why Hamada would be so specific until I cut down a tall dead Spruce=
=3D
about 5" or so at the base and counted the growth rings. The tree was abou=
=3D
t 30 years old. I was looking for stoking sticks 5" around and under becaus=
=3D
e any bigger became to big to conveniently stoke in the Bourry. That's when=
=3D
I realized an older tree would be bigger and then need splitting. My main =
=3D
stoke holes can take up to 10"x16" chunks in the Pig-nose and the Bourry
>> =3DA0box gets up to 5"x32"-35.5". Any bigger is to heavy to stoke and gi=
ve=3D
s the walls a real beating. Once a tree gets over 6" at the base one might =
=3D
as well let it grow more and keep it trimmed to make clear lumber.
>>
>> =3DA0I also learned most loggers haven't thought that way for a long tim=
e =3D
and clear cut with processors. They have left us with a bunch of Maple, Pop=
=3D
lar, Ash, Ironwood, Balsam, and Spruce sticks under 6" around. Also just be=
=3D
fore Christmas season we cut Balsam, Spruce, White Pine, and Cedar for deco=
=3D
rations so I have available more than the old single species I thought I ha=
=3D
d to use because that's what Hamada used and he made great pots. Hamada mad=
=3D
e great pots because he was Hamada not because he used 30 year old Red Pine=
=3D
. He and his firemen just didn't want to stoke anything heavier or split hu=
=3D
ge logs.
>>
>> =3DA0So I what I'm wondering is with these woods available in what ways =
or=3D
in what order would you solid fuel fanatics use these different woods in t=
=3D
he different stages of a 3 day or longer firing? I finally got to read Dick=
=3D
Lehmans description of arriving at a longer stoking pattern similar to wha=
=3D
t I was thinking in the mid '80's, although I was keeping the firebox small=
=3D
er, with similar advantages of letting the kiln fire unattended. At some st=
=3D
age we just want to make a dry heat, some to build up ash and keep the heat=
=3D
even, then some to get the temperature to climb, some to blast the load to=
=3D
melt the ash and glaze, some stoke to soak and/or side stoke. After making=
=3D
some adjustment repairs on the Pig-nose and Bourry box to get better contr=
=3D
ol of my coal pile at the throat arch with more air through the mouse-hole.=
=3D
..
>>
>> http://public.fotki.com/GindaUP/ca/kpap/uphwfkl3/bourry-box-mousehol.htm=
=3D
l
>>
>> ... I think I might be able to use some percentage of hardwood to keep a=
=3D
steady high heat with a good coal pile and still have room above the throa=
=3D
t arch for the skinny sticks to give off their fast burn and make the tempe=
=3D
rature rise...
>>
>> http://public.fotki.com/GindaUP/ca/kpap/uphwfkl3/hob-6in-wider-jpg.html
>>
>> =3DA0When those are spent the big stuff above the coal pile will hold th=
e =3D
slight rise until the next blasting stoke of skinny stuff. I used a similar=
=3D
pattern at the end of firing my smaller Hobagama and the big stuff was all=
=3D
pine but it lasted enough to do the trick. For some reason side stoking di=
=3D
d not drag ash through the front settings and most glazes were smooth and s=
=3D
hiny. Maybe I can find some old kiln logs and see if they say what I might =
=3D
have done. I might have pasted the primary and secondary air closed.
>>
>> =3DA0There is other tweaking I can do to the kiln later but I wanted to =
se=3D
e what others experience has been with different wood fuels and share it ju=
=3D
st in case some newcomers haven't seen previous discussions and I might hav=
=3D
e something new to think about so thanks and stay in there eh.
>>
>> Gary Navarre
>> Navarre Pottery
>> Navarre Enterprises
>> Norway, Michigan, USA
>> http://www.youtube.com/GindaUP
>> http://public.fotki.com/GindaUP/
>>
>
L TURNER on thu 5 aug 10
For those who want to select wood kiln fuel on the basis ash
quantities and properties, I suggest you look into the biomass
combustion research work done at the universities in Europe (and by
the US DOE), especially those in Denmark, Sweden, and Finland.
The focus is on power production and district heating but their
reports provide a valuable source of reliable peer reviewed analytical
data on fuel composition, heating value, and especially mineral matter
in the fuels.
The data - along with a few glaze calculations - will provide you with
some insight into why you get what you get from what you burn (and
perhaps, why you don't get what you want).
Regards,
L. Turner
The Woodlands, TX
gsomdahl on fri 6 aug 10
I've fired I several different wood and soda kilns. They all were hard
brick and stalled around 2100F. Cone 1 would be down and we would see
progression through higher cones, when they were present, and a color
change from orange to yellow, but the temperature changed little. The
conclusion I've reached is that the furniture and the hard bricks needed
to reach a temperature where they radiate heat back to the interior of
the kiln. That is, everything needs to catch up, then the temperature
would take off again. Now I just plan a soak at 2100F until cone 5
drops. Calling it a soak, instead of a stall, removes the stress of that
time in the firing.
Relax, Gene
On 08/05/2010 01:14 PM, tony clennell wrote:
> James wrote:
>
> We gain temperature quite readily, except for two sticking points at
>
>> 1400 degrees F and 2100 degrees F (probably a flaw in the kiln
>> design).
>>
> James: I don't think it is necessarily a design flaw. Every wood kiln
> I have fired has stalled around the two temperatures you mention. I
> call this the time to burp or fart the kiln period. As I understand it
> for every 690F that the temperature in the kiln rises the volume of
> gases doubles. So with that in mind you can see 1400 and 2100 F are
> critical times in the firing cycle. This usually has me putting in
> less wood more often to get it to move this gas thru it's bowels so it
> can eat some more. Especially the stall at 2100 when I get thru that
> the kiln is hot to trot and I can go back to a normal charge of wood
> in the firebox.
> Bon feu!
> Tony
>
>
--
This is a post only account. Send replies to "gene" at my ".com" domain nam=
ed "somdahl".
| |
|
