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cone 6/7 dilema

updated tue 25 aug 98


John Hesselberth on sat 22 aug 98

From time to time the problem of Cones 6 and 7 falling nearly
simultaneously has been discussed in this forum. I just had some
conversations with a very helpful person at Orton on this subject and
thought some members of the group might be interested in what I learned.

Orton is very aware that 6 and 7 fall very close together--nominally
about 25 deg F apart-- and they, in at least one case, produced a lot
that was even closer. They have tried to raise the temperature for Cone
7, but have failed. Some of the specific materials used start to act up
at the higher temperature and give unpredictable results.

What they have done is to bring out a Cone 5 1/2 which falls halfway
between 5 and 6. However Cone 5 1/2 is only available in the Large
self-supporting style. When I told this person that my supplier didn't
recognize Cone 5 1/2's existence he said to have them call Orton. It is

Hope this is useful to you.

John Hesselberth
Frog Pond Pottery
Pocopson, PA 19366 USA
visit my web site at

Linda Blossom on sun 23 aug 98

Just to add to the confusion. I remember when there was a discussion about =
changes in the cone 6's and had even found some old ones and fired them next=
the new ones. Now the sixes are acting out again. For the longest time I =
been putting cone 6 down at a range of 1185 and often at 1200 with a firing =
19 hours when I fire electric. (single fire, includes candle period of four
hours and one hour rise with a 30 min soak). Then those sixes started =
flatter and flatter so I started backing up and now get a good six with a =
at 2:00 at 1170 and 19 hour fire. Anyone else noticing this?
Linda Blossom
2366 Slaterville Rd.
Ithaca, NY 14850

lpskeen on mon 24 aug 98

Linda Blossom wrote:
> Just to add to the confusion. I remember when there was a discussion about th

Am I hearing you say that there is a problem with Orton ^6 cones?
They're not breaking/falling at the right temperature? Does this apply
to the small cones for electric kilns too?
Lisa Skeen ICQ# 15554910
Living Tree Pottery & Soaps
"We will have to repent in this generation not merely for the hateful
words and actions of the bad people, but for the appalling silence of
the good people." -- Dr. M. L. King, Jr. 4/16/63