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cone numbering

updated mon 3 jan 00

 

David Hendley on tue 28 dec 99

The numbering system for cones is no more
difficult to understand than historical dates.
Start at the birth of Christ (0), and go in both
directions, with the numbers getting larger in
both directions.
One set of numbers is called B.C., and one set
is called A.D.
"B.C." is not meaningless and dismissed, just as
the "0" before the cone number of the lower
temperature cones should not be.

The end point temperatures and numbering of cones
was based on empirical formulas for the cones.
I don't remember the exact numbers, but if you look
at the unity formula for cone 6, you will find that
the fluxes add up to 1 (unity formula), alumina is
.6, and silica is 6.0.
For cone 10, the fluxes stay at 1, and alumina is
1.0, silica is 10.0.

It makes perfect sense viewed this way. Again, I
don't remember the exact numbers, the ones I quoted
above are just examples of the idea.
This logical system holds up for most of the spectrum
of cones, but breaks down at the very low temperatures.
I have formulas with tested and proven recipes for
several cones that would allow you to make your own
cones. If anyone is interested, I will look this up and post it.
Harry Davis also goes into this in his book, "The Potter's
Alternative".

--
David Hendley
Maydelle, Texas
hendley@tyler.net
http://www.farmpots.com/






----- Original Message -----
From: elizabeth priddy
To:
Sent: Monday, December 27, 1999 6:50 PM
Subject: Re: stoneware bisque, cone numbering


| ----------------------------Original message----------------------------
| the numbering system for cones is about the
| most asinine thing I have ever encountered in
| clay.
|
| If you describe it as a number line with 00 at
| the middle, you can make people understand it
| easily enough, but for the rest of the world,
| the '0' when placed before a number is
| meaningless and dismissed. This is why they
| do this.
|
|
| This is vague, but I don't want to diseminate
| misinformation so I won't declare that the
| something I am referring to is lead, maybe
| someone can clarify this detail for me:
|
|
| I think that cone 0 is supposed to be the
| particular melting temperature for something
| and that everything else was named relative
| to this particular point, but it sure seems
| like someone would have changed this at some
| later, but pre-modern, time.
|
| I, unfortunately, think it is too late and
| we are stuck with it.
| ---
| Elizabeth Priddy
|
| email: epriddy@usa.net
| http://www.angelfire.com/nc/clayworkshop
| Clay: 12,000 yrs and still fresh!
|

Hank Murrow on wed 29 dec 99

Very nice answer David; From C/27 to C/010 the fluxes are held at .3K2O +
.7 CaO; while the Al/Si vary in a 1-10 way down to C/1. Lower than C/010
the fluxes change to .5 Na2O and .5 PbO; and 1 B2O3 is added too. Thanks,
Hank Murrow


>----------------------------Original message----------------------------
>The numbering system for cones is no more
>difficult to understand than historical dates.
>Start at the birth of Christ (0), and go in both
>directions, with the numbers getting larger in
>both directions.
>One set of numbers is called B.C., and one set
>is called A.D.
>"B.C." is not meaningless and dismissed, just as
>the "0" before the cone number of the lower
>temperature cones should not be.
>
>The end point temperatures and numbering of cones
>was based on empirical formulas for the cones.
>I don't remember the exact numbers, but if you look
>at the unity formula for cone 6, you will find that
>the fluxes add up to 1 (unity formula), alumina is
>.6, and silica is 6.0.
>For cone 10, the fluxes stay at 1, and alumina is
>1.0, silica is 10.0.
>
>It makes perfect sense viewed this way. Again, I
>don't remember the exact numbers, the ones I quoted
>above are just examples of the idea.
>This logical system holds up for most of the spectrum
>of cones, but breaks down at the very low temperatures.
>I have formulas with tested and proven recipes for
>several cones that would allow you to make your own
>cones. If anyone is interested, I will look this up and post it.
>Harry Davis also goes into this in his book, "The Potter's
>Alternative".
>
>--
>David Hendley
>Maydelle, Texas
>hendley@tyler.net
>http://www.farmpots.com/
>
>
>
>
>
>
>----- Original Message -----
>From: elizabeth priddy
>To:
>Sent: Monday, December 27, 1999 6:50 PM
>Subject: Re: stoneware bisque, cone numbering
>
>
>| ----------------------------Original message----------------------------
>| the numbering system for cones is about the
>| most asinine thing I have ever encountered in
>| clay.
>|
>| If you describe it as a number line with 00 at
>| the middle, you can make people understand it
>| easily enough, but for the rest of the world,
>| the '0' when placed before a number is
>| meaningless and dismissed. This is why they
>| do this.
>|
>|
>| This is vague, but I don't want to diseminate
>| misinformation so I won't declare that the
>| something I am referring to is lead, maybe
>| someone can clarify this detail for me:
>|
>|
>| I think that cone 0 is supposed to be the
>| particular melting temperature for something
>| and that everything else was named relative
>| to this particular point, but it sure seems
>| like someone would have changed this at some
>| later, but pre-modern, time.
>|
>| I, unfortunately, think it is too late and
>| we are stuck with it.
>| ---
>| Elizabeth Priddy
>|
>| email: epriddy@usa.net
>| http://www.angelfire.com/nc/clayworkshop
>| Clay: 12,000 yrs and still fresh!
>|

Tom Wirt on wed 29 dec 99

> I have formulas with tested and proven recipes for
> several cones that would allow you to make your own
> cones. If anyone is interested, I will look this up and post it.
> Harry Davis also goes into this in his book, "The Potter's
> Alternative".
>


David...yes, I'd be very interested in the formulas. I want to try some
self made cones, but also want to look into how the formulas compare to
claybodies for the different temps.

Thanks beforehand

Tom Wirt

tgschs10 on sun 2 jan 00

To All,

For those of you that have trouble converting a specific cone into a
Farenheit temperature, I have a rule of thumb that helps. Assume cone 0 to
be 2000 F; add 30 F for each cone above 0; e.g., cone 10 = 2000 + [10 x 30]
= 2300; cone 5 = 2000 + [5 x 30] = 2150. For cones below 0 subtract 30 for
each cone; cone 05 = 2000 - [5 x 30] = 1850. Okay so it doesn't work
perfectly but it does help.

Tom Sawyer
Orlando, Florida
tgschs10@msn.com
----- Original Message -----
From: "Hank Murrow"
To:
Sent: Wednesday, December 29, 1999 10:56 AM
Subject: Re: cone numbering


> ----------------------------Original message----------------------------
> Very nice answer David; From C/27 to C/010 the fluxes are held at .3K2O +
> .7 CaO; while the Al/Si vary in a 1-10 way down to C/1. Lower than C/010
> the fluxes change to .5 Na2O and .5 PbO; and 1 B2O3 is added too. Thanks,
> Hank Murrow
>
>
> >----------------------------Original message----------------------------
> >The numbering system for cones is no more
> >difficult to understand than historical dates.
> >Start at the birth of Christ (0), and go in both
> >directions, with the numbers getting larger in
> >both directions.
> >One set of numbers is called B.C., and one set
> >is called A.D.
> >"B.C." is not meaningless and dismissed, just as
> >the "0" before the cone number of the lower
> >temperature cones should not be.
> >
> >The end point temperatures and numbering of cones
> >was based on empirical formulas for the cones.
> >I don't remember the exact numbers, but if you look
> >at the unity formula for cone 6, you will find that
> >the fluxes add up to 1 (unity formula), alumina is
> >.6, and silica is 6.0.
> >For cone 10, the fluxes stay at 1, and alumina is
> >1.0, silica is 10.0.
> >
> >It makes perfect sense viewed this way. Again, I
> >don't remember the exact numbers, the ones I quoted
> >above are just examples of the idea.
> >This logical system holds up for most of the spectrum
> >of cones, but breaks down at the very low temperatures.
> >I have formulas with tested and proven recipes for
> >several cones that would allow you to make your own
> >cones. If anyone is interested, I will look this up and post it.
> >Harry Davis also goes into this in his book, "The Potter's
> >Alternative".
> >
> >--
> >David Hendley
> >Maydelle, Texas
> >hendley@tyler.net
> >http://www.farmpots.com/
> >
> >
> >
> >
> >
> >
> >----- Original Message -----
> >From: elizabeth priddy
> >To:
> >Sent: Monday, December 27, 1999 6:50 PM
> >Subject: Re: stoneware bisque, cone numbering
> >
> >
> >| ----------------------------Original
message----------------------------
> >| the numbering system for cones is about the
> >| most asinine thing I have ever encountered in
> >| clay.
> >|
> >| If you describe it as a number line with 00 at
> >| the middle, you can make people understand it
> >| easily enough, but for the rest of the world,
> >| the '0' when placed before a number is
> >| meaningless and dismissed. This is why they
> >| do this.
> >|
> >|
> >| This is vague, but I don't want to diseminate
> >| misinformation so I won't declare that the
> >| something I am referring to is lead, maybe
> >| someone can clarify this detail for me:
> >|
> >|
> >| I think that cone 0 is supposed to be the
> >| particular melting temperature for something
> >| and that everything else was named relative
> >| to this particular point, but it sure seems
> >| like someone would have changed this at some
> >| later, but pre-modern, time.
> >|
> >| I, unfortunately, think it is too late and
> >| we are stuck with it.
> >| ---
> >| Elizabeth Priddy
> >|
> >| email: epriddy@usa.net
> >| http://www.angelfire.com/nc/clayworkshop
> >| Clay: 12,000 yrs and still fresh!
> >|
>