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indication of temperature

updated sat 4 jan 03

 

Earl Brunner on tue 31 dec 02


You need to compare that range to the range of cones. For example that=20
range, according to one of my books is right at Orton cone 6-7 (you=20
guys use seger cones though, right? You might need to do a conversion).=20
You can program most controllers either way, by cone, or by temperature.

Earl Brunner

Waltraud Koestler wrote:
> Hello,
>=20
> I've got a question about the indication of the firing range on
> clay
> bags.
>=20
> I'd try different porcelain bodies. The suppliers indicate the
> firing
> range for the bodies for example as follows
>=20
> oxidation firing: 1220 to 1240 C. (Limoges TM10)
>=20
> What does it mean?
> The temperature I can set on the controller of my electric kiln
> or is
> this the falling temperature of the cones?
>=20
> Because of the costs and supplying I'd like to decide which
> porcelain
> body is suitable for me before I order. One aspect is the firin=
g
> range.
>=20
> Thank you in advance for the help!
>=20
> I wish all clayart members and their families a Happy New Year =
!!!
>=20
>=20
> Waltraud
>=20
> --Germany
>=20
>=20
>=20
>=20
>=20
>=20
>=20
> http://www.planet-b.net - Das Internetportal f=FCr
> Bertelsmann-Mitarbeiter und Ihre Familien.
>=20
> _______________________________________________________________________=
_______=20
> Send postings to clayart@lsv.ceramics.org You may look at the archives=20
> for the list or change your subscription settings from=20
> http://www.ceramics.org/clayart/ Moderator of the list is Mel Jacobson=20
> who may be reached at melpots@pclink.com.

Waltraud Koestler on tue 31 dec 02


free email, free, branded, web based, free web based email, communicatio=
ns, internet, software, advertising banners, e-mail, free software'>ad>
lockquote>Hello,



I've got a question about the indication of the firing range on clay R>
bags.



I'd try different porcelain bodies. The suppliers indicate the firing <=
BR>
range for the bodies for example as follows



     oxidation firing: 1220 to 1240 C. (Limoges TM10)R>


What does it mean?

The temperature I can set on the controller of my electric kiln or is <=
BR>
this the falling temperature of the cones?



Because of the costs and supplying I'd like to decide which porcelain <=
BR>
body is suitable for me before I order. One aspect is the firing

range.



Thank you in advance for the help!



I wish all clayart members and their families a Happy New Year !!!





Waltraud



--Germany








http://www.p=
lanet-b.net - Das Internetportal f=FCr Bertelsmann-Mitarbeiter und Ihre =
Familien.



Snail Scott on tue 31 dec 02


At 07:10 PM 12/31/02 +0100, Waltraud wrote:=20

...oxidation firing: 1220 to 1240 C. (Limoges TM10)

What does it mean?=20

The temperature I can set on the controller of my electric kiln or is=20

this the falling temperature of the cones?=20



<<<<<<<<


When temperatures are given in degrees, that can=20

mean a range of different equivalents in cones,=20

because cones don't just measure temperature, they=20

measure heat-work, which is a more accurate way to=20

judge what is really happening to your clay. A slow=20

firing to 1220=BAC can be equal in heat-work to a=20

faster firing to 1240=BAC. (These temperatures are in=20

the range of an Orton ^6, by the way.)=20


Your exact firing style will make a difference in=20

how you judge temperature. I prefer to use cones=20

to see when a firing is at its peak, since they=20

naturally compansate for any variation in speed of=20

firing. If you prefer to use an electronic=20

controller, that's fine, too, but in that case you=20

need to keep your firing schedule consistent, since=20

that temperature won't correspond to the same amount=20

of heat-work if the firing is much faster or slower.

You will have to experiment with the proper firing=20

temperature for optimum results, especially if you=20

use glazes. The glazes, rather than the clay, will=20

probably end up being the factor which determines=20

your firing schedule and temperature, or cone.


I hope this explains a little of what you wanted=20

to know!=20


-Snail

Martin Howard on fri 3 jan 03


This question from Waltraud and answered by Snail links to my question which
seems have got lost when the Mel's site went down last weekend.

What is the agreed "Clayart" number of degrees we should adjust the top
point of our firings for each 20 minutes or so of soak?

I have read 10 degrees C for 20 minutes soak.
Is that what the experts on the list are using?

I've just had a new controller fitted and first over fired, then underfired,
trying to get it just right.

Martin Howard
Webbs Cottage Pottery
Woolpits Road, Great Saling
BRAINTREE, Essex CM7 5DZ
01371 850 423
martin@webbscottage.co.uk
http://www.webbscottage.co.uk
Updated 2nd January 2003

Jeff on fri 3 jan 03


My problems when I got my skutt controller were related to how far I put the
thermocouple into the kiln. I'm not a good one for writing things down, but
I think that having the thermocouple too far in the kiln resulted in
artificially high readings. (kiln cooler than the computer registered)

Get that sucker set, and don't move it. Get it close then fine tune with
the temperature settings of the controller. So what if your top end winds
up reading 5-10 degrees more or less than "the book" its getting that cone
to bend the desired amount that counts. (and of course a controlled cool
down)


The guys at skutt were very patient with me as were JH & RR, there were
several emails back / forth when I was initially setting my controller.
And it case I didn't say thanks then, I'll say it now,

Thanks JH, RR and to the guys at skutt!

Jeff

-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG]On Behalf Of Martin Howard
Sent: Friday, January 03, 2003 10:59 AM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Indication of temperature

This question from Waltraud and answered by Snail links to my question which
seems have got lost when the Mel's site went down last weekend.

What is the agreed "Clayart" number of degrees we should adjust the top
point of our firings for each 20 minutes or so of soak?

I have read 10 degrees C for 20 minutes soak.
Is that what the experts on the list are using?

I've just had a new controller fitted and first over fired, then underfired,
trying to get it just right.

Martin Howard
Webbs Cottage Pottery
Woolpits Road, Great Saling
BRAINTREE, Essex CM7 5DZ
01371 850 423
martin@webbscottage.co.uk
http://www.webbscottage.co.uk
Updated 2nd January 2003

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