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fw: 02 bleed in a wood kiln

updated thu 11 aug 11

 

David Woof on tue 9 aug 11


Hi Gary=3D2C

you are at something like 600' elevation so you have plenty of the big "O" =
=3D
available if you know how to access it.
=3D20
Everyone knows where to stick the wood but many folks struggle with the pri=
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nciples of feeding the fire.

The function of the Chimney on many kilns is misunderstood by kiln builders=
=3D
and firers as related to your problem.
=3D20
Before you figure out how to stoke it=3D2C build the chimney bigger than a=
ll=3D
the sage advice from all the "experts" with at least=3D20
12 passive damper pull bricks to regulate the draft which controls the amo=
=3D
unt of oxygen that is pulled thru the air intakes.

Now your kiln is a "musical instrument" you can play like a flute=3D3B bal=
an=3D
cing intake and exit.
=3D20
Now stoke again when your (previous) stoke burns down and collapses into c=
=3D
oals and the flame licks back into the chamber. =3D20
Now the fire is hungry and you've just had the end of stoke heat rise. U=
=3D
se your pyrometer as a learning tool but don't fire by it!
=3D20
Don't fire by counting sticks and or minutes for each stoke(this is just p=
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lain ignorant)!!! Your kiln isn't firing by such a=3D20
schedule so read the fire and feed the kiln when it asks for more!!!
=3D20
If you do happen to get over zealous with your stokes (read=3D3B over cont=
ro=3D
lling and=3D20
freaked out because it seems to be stalling) relax and let it burn down to =
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clear its throat.
=3D20
Balance the intakes and mouse holes so that you don't get a choke up of de=
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ad ash and smothered charcoal. =3D20
A too small chimney and too much open at the intakes makes for a lazy fire.=
=3D
=3D20
Your chimney is the heart of the kiln=3D3B it corresponds to the blowers on=
a=3D
gas burner system=3D2C=3D20
tune the intakes around this function. You can suck a lot of Oxygen through=
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some pretty small holes up front if the Chimney is=3D20
drawing as it should.
=3D20
Pay attention to your chimney! It is far too easy to get hung up on the id=
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ea of gas kiln size flues for wood fire=3D2C tapers=3D2C formulas=3D2C and =
this s=3D
ort of thing. Mel and Nils have a system of practical thought and applicat=
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ion regarding reduction of flue size vs. the old and accepted gas kiln flue=
=3D
sizes=3D3B but it is my observation that a good number of folks aren't pay=
in=3D
g attention as they try part of the advice=3D3B ignore parts and them attes=
t =3D
that it doesn't work. =3D20

Same plays for wood kilns. I read much=3D3B "well I think" and other handy =
da=3D
ndy "sidewalk advice" from would be experts who lack experience and underst=
=3D
anding. Seems everyone wants it quick without bothering to learn the prin=
=3D
ciples that would empower them to really get the most from their wood firin=
=3D
g experience. =3D20

Whether you bother to think about what I've said or not is no skin off my n=
=3D
ose but I hope you do. I have never published anything because I haven't t=
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aken time to write a book or submit anything to Mel's book either but smart=
=3D
folks over the years have thought about what I've posted and made it their=
=3D
own. Hope you do=3D2C it will smooth out your firing experience.

David Woof....Clarkdale=3D2C Arizona.......wood kiln designer=3D2C innovato=
r=3D2C=3D
inventor=3D2C builder=3D2C and firer of user friendly no fuss wood fueled =
kiln=3D
s because I love doing it as much as life itself. =3D20

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