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raku fire can i use coal

updated fri 7 oct 11

 

Lee on wed 5 oct 11


Coal was a traditonal fuel for ceramic kilns both in European bottle
kilns and in China . You might have to experiment, but you should be
able to figure it out.


--
=3DA0Lee Love in Minneapolis
http://mingeisota.blogspot.com/

=3DA0"Ta tIr na n-=3DF3g ar chul an tI=3D97tIr dlainn trina ch=3DE9ile"=3D9=
7that is, =3D
"The
land of eternal youth is behind the house, a beautiful land fluent
within itself." -- John O'Donohue

Llewellyn Kouba on wed 5 oct 11


Dear Readers.

This fall 4 of us potters are getting together to try a 'new raku kiln.
We have on our grounds an old incinerator and I have wondered for years
if it might not work as a raku type kiln? The thing is made of cinder
block and a layer of firebrick on the inside with metal grates and a
chimney flue. The inside dimensions of the fire chamber is approximately
3 x 3 x 5 feet. It is a bit below grates where you would toss in the
fuel source but all in all we are thinking if we can keep this thing
stoked long enough we may just get some effects with colorants and so on
with low fired work. Ash Coulee Pottery is going to bring along a
pyrometer so we can get an idea of the heat we might get. We have our
wood cut and ready. We also wonder if we can supplement hard coal along
with the wood to get it to burn hotter. Any input on the pros and cons
with adding the coal for fuel, and any observations would be
appreciated. You can access a few photos here:
http://www.assumptionabbey.com/Pottery/page198.html

Llewellyn


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jonathan byler on wed 5 oct 11


probably not. coal tends to have a fairly high sulfur content, which
is usually detrimental to ceramic processes. coke on the other hand
might work?

On Oct 5, 2011, at 4:59 PM, Llewellyn Kouba wrote:

> Dear Readers.
>
> This fall 4 of us potters are getting together to try a 'new raku
> kiln.
> We have on our grounds an old incinerator and I have wondered for
> years
> if it might not work as a raku type kiln? The thing is made of cinder
> block and a layer of firebrick on the inside with metal grates and a
> chimney flue. The inside dimensions of the fire chamber is
> approximately
> 3 x 3 x 5 feet. It is a bit below grates where you would toss in the
> fuel source but all in all we are thinking if we can keep this thing
> stoked long enough we may just get some effects with colorants and
> so on
> with low fired work. Ash Coulee Pottery is going to bring along a
> pyrometer so we can get an idea of the heat we might get. We have our
> wood cut and ready. We also wonder if we can supplement hard coal
> along
> with the wood to get it to burn hotter. Any input on the pros and cons
> with adding the coal for fuel, and any observations would be
> appreciated. You can access a few photos here:
> http://www.assumptionabbey.com/Pottery/page198.html
>
> Llewellyn
>
>
> __________ Information from ESET NOD32 Antivirus, version of virus
> signature database 6520 (20111005) __________
>
> The message was checked by ESET NOD32 Antivirus.
>
> http://www.eset.com

Paul Herman on wed 5 oct 11


Llewellyn,

Coal has sulphur in it. I think you may not really want sulphur, it
has a reputation for producing undesirable results. In old kilns that
were fired with coal, everything was stacked in saggers.

Best wishes,

Paul Herman

Great Basin Pottery
Doyle, California US
www.greatbasinpottery.com/




On Oct 5, 2011, at 2:59 PM, Llewellyn Kouba wrote:

> Dear Readers.
>
> This fall 4 of us potters are getting together to try a 'new raku
> kiln.
> We have on our grounds an old incinerator and I have wondered for
> years
> if it might not work as a raku type kiln? The thing is made of cinder
> block and a layer of firebrick on the inside with metal grates and a
> chimney flue. The inside dimensions of the fire chamber is
> approximately
> 3 x 3 x 5 feet. It is a bit below grates where you would toss in the
> fuel source but all in all we are thinking if we can keep this thing
> stoked long enough we may just get some effects with colorants and
> so on
> with low fired work. Ash Coulee Pottery is going to bring along a
> pyrometer so we can get an idea of the heat we might get. We have our
> wood cut and ready. We also wonder if we can supplement hard coal
> along
> with the wood to get it to burn hotter. Any input on the pros and cons
> with adding the coal for fuel, and any observations would be
> appreciated. You can access a few photos here:
> http://www.assumptionabbey.com/Pottery/page198.html
>
> Llewellyn

Gregory on thu 6 oct 11


Brother,=3D20

Mastering Raku: Making Ware * Glazes * Building Kilns * Firing
By Steven Branfman has a section on firing and he writes about coal as a=
=3D

fuel source. Book is available at Amazon.

Greg

Steve Mills on thu 6 oct 11


You can use Coal, but you'll need a Saggar with a removable lid as a ware =
c=3D
hamber, as (as has been pointed out) the gasses it gives off are a problem.=
=3D20=3D

Coal or Coke fired Raku Style firing was done a lot over here before bottle=
d=3D
gas and appropriate burners were widely available.=3D20
As Mike pointed out Charcoal is a good sub, and a cheap hair-dryer makes a =
r=3D
easonable temporary blower.=3D20

Steve M


Steve Mills
Bath
UK
www.mudslinger.me.uk
Sent from my Ipod touch

On 5 Oct 2011, at 22:59, Llewellyn Kouba wrote:

> Dear Readers.
>=3D20
> This fall 4 of us potters are getting together to try a 'new raku kiln.
> We have on our grounds an old incinerator and I have wondered for years
> if it might not work as a raku type kiln? The thing is made of cinder
> block and a layer of firebrick on the inside with metal grates and a
> chimney flue. The inside dimensions of the fire chamber is approximately
> 3 x 3 x 5 feet. It is a bit below grates where you would toss in the
> fuel source but all in all we are thinking if we can keep this thing
> stoked long enough we may just get some effects with colorants and so on
> with low fired work. Ash Coulee Pottery is going to bring along a
> pyrometer so we can get an idea of the heat we might get. We have our
> wood cut and ready. We also wonder if we can supplement hard coal along
> with the wood to get it to burn hotter. Any input on the pros and cons
> with adding the coal for fuel, and any observations would be
> appreciated. You can access a few photos here:
> http://www.assumptionabbey.com/Pottery/page198.html
>=3D20
> Llewellyn
>=3D20
>=3D20
> __________ Information from ESET NOD32 Antivirus, version of virus signat=
u=3D
re database 6520 (20111005) __________
>=3D20
> The message was checked by ESET NOD32 Antivirus.
>=3D20
> http://www.eset.com

Mike on thu 6 oct 11


Looks like a fun experiment. I don't think there is any question you
could get it to raku temps firing with wood and coal, it might be a good
idea to have a blower on hand, just in case.
How hot is that old incinerator designed to go? You might want to look
into that before taking it too high. It might not last long otherwise.

I've fired little clamshell style kilns made from clay with just
charcoal and a blower, and there is no problem getting them hot enough
to melt ash, but they wear out after a dozen or so firings.

Mike
in Taku, Japan

http://karatsupots.com
http://karatsupots.blogspot.com

Workshop in Taku 2012: The Simple Teabowl, May 12 - 18

http://karatsupots.com/workshop2012/2012home.html

http://workshopintaku2012.blogspot.com/


(2011/10/06 6:59), Llewellyn Kouba wrote:
> Dear Readers.
>
> This fall 4 of us potters are getting together to try a 'new raku kiln.
> We have on our grounds an old incinerator and I have wondered for years
> if it might not work as a raku type kiln? The thing is made of cinder
> block and a layer of firebrick on the inside with metal grates and a
> chimney flue. The inside dimensions of the fire chamber is approximately
> 3 x 3 x 5 feet. It is a bit below grates where you would toss in the
> fuel source but all in all we are thinking if we can keep this thing
> stoked long enough we may just get some effects with colorants and so on
> with low fired work. Ash Coulee Pottery is going to bring along a
> pyrometer so we can get an idea of the heat we might get. We have our
> wood cut and ready. We also wonder if we can supplement hard coal along
> with the wood to get it to burn hotter. Any input on the pros and cons
> with adding the coal for fuel, and any observations would be
> appreciated. You can access a few photos here:
> http://www.assumptionabbey.com/Pottery/page198.html
>
> Llewellyn
>
>
> __________ Information from ESET NOD32 Antivirus, version of virus
> signature database 6520 (20111005) __________
>
> The message was checked by ESET NOD32 Antivirus.
>
> http://www.eset.com
>