John Bacon on tue 2 mar 99
I teach a high school ceramics class and am just getting started in trying
some sawdust fires (largely following the procedure outlined in an article
about Martha Puckett in the Fall '98 edition of Pottery Making
Illustrated). We are using 5 gallon & 20 gallon metal containers. It seems
like a different, inexpensive, manageable firing option that our kids will
really enjoy. Don't know much yet, just that you can't ever really predict
what is going to come out at the end. Having said that (and mostly
believing it), does anyone out there have any advice about what coloring
effects can sometimes be controlled through various additives/procedures ?
I'm limiting my early experiments to the following factors to try to
establish some kind of baseline knowledge/experience that someday I may
build on:
length of flaming time
length of smoking time
pine sawdust
pine and/or oak wood chips (is there any difference?)
proximity of sawdust to pots
proximity of wood chips to pots
salt (any difference between rock salt and table salt?)
copper sulfate (any difference between the stuff I get at the feed store
and the stuff I can get at the pottery store?)
horse manure (mostly from dark brown horses, but some from a light tan
horse)
horse mane & tail (same horses)
Early experiments have produced some cool effects, but I don't yet have the
experience to know which factors are producing which effects. I'd really
like to someday have some semi-predictable results that I can pass along to
our students so that their limited opportunities with sawdust firing are
educational and exciting.
Thanks, John Bacon
John Bacon on tue 2 mar 99
I teach a high school ceramics class and am just getting started in trying
some sawdust fires (largely following the procedure outlined in an article
about Martha Puckett in the Fall '98 edition of Pottery Making
Illustrated). We are using 5 gallon & 20 gallon metal containers. It seems
like a different, inexpensive, manageable firing option that our kids will
really enjoy. Don't know much yet, just that you can't ever really predict
what is going to come out at the end. Having said that (and mostly
believing it), does anyone out there have any advice about what coloring
effects can sometimes be controlled through various additives/procedures ?
I'm limiting my early experiments to the following factors to try to
establish some kind of baseline knowledge/experience that someday I may
build on:
length of flaming time
length of smoking time
pine sawdust
pine and/or oak wood chips (is there any difference?)
proximity of sawdust to pots
proximity of wood chips to pots
salt (any difference between rock salt and table salt?)
copper sulfate (any difference between the stuff I get at the feed store
and the stuff I can get at the pottery store?)
horse manure (mostly from dark brown horses, but some from a light tan
horse)
horse mane & tail (same horses)
Early experiments have produced some cool effects, but I don't yet have the
experience to know which factors are producing which effects. I'd really
like to someday have some semi-predictable results that I can pass along to
our students so that their limited opportunities with sawdust firing are
educational and exciting.
Thanks, John Bacon
Dannon Rhudy on wed 3 mar 99
It sounds to me as though you are off to a good start. The materials you are
using are perfectly adequate. Results are unpredictable, as you mention.
My own fairly extensive experience has been:
The materials used such as sawdust, pine straw, other combustibles
make no real difference that is specifically definable. They are
essentially carbon-producers. Carbon is carbon, no matter the source.
Things like pine straw, long grasses and seaweed can sometimes produce
interesting lines on the surface. And sometimes not. If you are not
getting sufficient blacks from your firings, you could add a bit of charcoal
and see if that makes richer blacks. But it sounds as though you like what
you're seeing so far.
As to the salts etc. listed, again my experience:
Copper sulfate makes medium to dark reds, sometimes pinks. Sometimes
green, which is usually fugitive. But not always. The source
is immaterial, farm store is good/cheap. You might try dissolving the
copper in water, soaking a bunch of sawdust in it (don't use from treated
wood, fumes are very toxic). Then pack the sawdust close around the
pots. Get some great blushes of color that way. You can also soak old
bits of terrycloth in copper, wrap pots. Works.
Salt is salt, table or rock, same stuff. Produces peach/orange/reddish
tones.
You could try some wisps of steel wool, wrapped around. Makes a
chocolate brown (and I do mean wisps; large pieces make rough
surfaces). If you use the kind that have soap in them, then you'll get
streaks/lumps/blobs of a pale turqoise blue glaze from it - borax.
Manure is pretty much manure. Some differences horse/cattle, but
mostly makes no observable difference. Now of course, if you happened
to have access to some Rhode Island Red chickens....
Keep on keepin' on. Sounds like you're having fun, doing a good job.
Regards,
Dannon Rhudy
potter@koyote.com
At 07:46 AM 3/2/99 EST, you wrote:
>----------------------------Original message----------------------------
>I teach a high school ceramics class and am just getting started in trying
>some sawdust fires (largely following the procedure outlined in an article
>about Martha Puckett in the Fall '98 edition of Pottery Making
>Illustrated). We are using 5 gallon & 20 gallon metal containers. It seems
>like a different, inexpensive, manageable firing option that our kids will
>really enjoy. Don't know much yet, just that you can't ever really predict
>what is going to come out at the end. Having said that (and mostly
>believing it), does anyone out there have any advice about what coloring
>effects can sometimes be controlled through various additives/procedures ?
>I'm limiting my early experiments to the following factors to try to
>establish some kind of baseline knowledge/experience that someday I may
>build on:
> length of flaming time
> length of smoking time
> pine sawdust
> pine and/or oak wood chips (is there any difference?)
> proximity of sawdust to pots
> proximity of wood chips to pots
> salt (any difference between rock salt and table salt?)
> copper sulfate (any difference between the stuff I get at the feed
store
>and the stuff I can get at the pottery store?)
> horse manure (mostly from dark brown horses, but some from a light
tan
>horse)
> horse mane & tail (same horses)
>Early experiments have produced some cool effects, but I don't yet have the
>experience to know which factors are producing which effects. I'd really
>like to someday have some semi-predictable results that I can pass along to
>our students so that their limited opportunities with sawdust firing are
>educational and exciting.
>
>Thanks, John Bacon
>
Marcia Selsor on wed 3 mar 99
I have to laugh at your description of the color of horses providing your
manure. I really don't think that matters much. I know in dung firing what
matters is field fed or grain fed.
As to oak or pine, sometimes pine leaves pitch/tar scars on the surface. I use
sawdust from an exhaust system of a hardwood cabinet maker. Hard wood doesn't
have the pitch problem.
A while back a woman from Fla. in an article in CM mentioned using horse urine
soaked sawdust. She called it a magic potion. I tried this and my friends with
horses really appreciated my delivery and pickup of the sawdust. It does leave
some nice surfaces and some color variation.
Have fun.
Marcia in Montana
John Bacon wrote:
>
> ----------------------------Original message----------------------------
> I teach a high school ceramics class and am just getting started in trying
> some sawdust fires (largely following the procedure outlined in an article
> about Martha Puckett in the Fall '98 edition of Pottery Making
> Illustrated). We are using 5 gallon & 20 gallon metal containers. It seems
> like a different, inexpensive, manageable firing option that our kids will
> really enjoy. Don't know much yet, just that you can't ever really predict
> what is going to come out at the end. Having said that (and mostly
> believing it), does anyone out there have any advice about what coloring
> effects can sometimes be controlled through various additives/procedures ?
> I'm limiting my early experiments to the following factors to try to
> establish some kind of baseline knowledge/experience that someday I may
> build on:
> length of flaming time
> length of smoking time
> pine sawdust
> pine and/or oak wood chips (is there any difference?)
> proximity of sawdust to pots
> proximity of wood chips to pots
> salt (any difference between rock salt and table salt?)
> copper sulfate (any difference between the stuff I get at the feed sto
> and the stuff I can get at the pottery store?)
> horse manure (mostly from dark brown horses, but some from a light tan
> horse)
> horse mane & tail (same horses)
> Early experiments have produced some cool effects, but I don't yet have the
> experience to know which factors are producing which effects. I'd really
> like to someday have some semi-predictable results that I can pass along to
> our students so that their limited opportunities with sawdust firing are
> educational and exciting.
>
> Thanks, John Bacon
--
Marcia Selsor
selsor@imt.net
http://www.imt.net/~mjbmls
http://www.imt.net/~mjbmls/spain99.html
Joy Holdread on sat 6 mar 99
> Manure is pretty much manure. Some differences horse/cattle, but
> mostly makes no observable difference. Now of course, if you happened
> to have access to some Rhode Island Red chickens....
> Dannon Rhudy potter@koyote.com
Well as a matter of fact I do. How about Bard Rocks? Were you being silly or
is the high nitration poop the latest poop?
Joy in Tucson
De Witt on sun 7 mar 99
.. Now of course, if you happened
>> to have access to some Rhode Island Red chickens....
>> Dannon Rhudy potter@koyote.com
>
>Well as a matter of fact I do. How about Bard Rocks? Were you being silly
or
>is the high nitration poop the latest poop?
Ok. here I go again. I know that the Araconna Chicken processes copper in
it's body differently than other chickens (that is why they lay green eggs)
would that make a difference. We keep ours on saw dust but it mulches down
to dirt I might take the top layer for my next sawdust firing if I can ever
find anyone to bisque my next load of pots. (no fun not having a kiln).
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