Paul Borian on mon 27 nov 06
I have seen this clay listed in some catalogs as a stoneware and others as
a ball clay. Does anyone know why this is?
I have been using about 10% in my cone 11 body and the main reason i
started using it is because i thought it was a stoneware. I already use old
hickory #5 for my ball clay for it's whiteness and refractoryness (sp?).
But if foundry hill is just another type of ball clay i could probably
eliminate it to make things simpler.
Can anyone comment on this?
thanks,
Paul
John Boyd on tue 28 nov 06
Dear Paul,
According to H.C. Spinks, they produce ball clays and I don't see New Foundry Hill Creme listed as separate. Their technical documents and MSDS list it as a ball clay. It is probably associated with stoneware because it is fine-grained, lends plasticity to a body and is darker than the usual ball clays we use. It is also a monmorillionite type clay and not a kandite, another reason it may be classified as a stoneware by some. I use quite a bit of it in an ersatz bizen clay body formula for this very reason. Before you toss it out of the recipe, I would consider how you fire the clay, and what you want in terms of workability and fired color. If you fire with wood or soda, it may be giving you some chromatic effects you would lose by switching it all to the Old Hickory #5. If purity of color is what you seek for glazes, then you should toss it, because it has manganese as well as iron traces. I hope this is of some help
Sincerely,
John Boyd
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Eleanora Eden on wed 29 nov 06
Hi Paul,
I have had this question myself. Digitalfire website categorizes it as a stoneware.
If memory serves, some of clayart's experts call it a ball clay. I did test bars of all
of my clay materials to ^3 which is where I am going with it, and it seems to be
in the middle somewhere at this temp. So I call it kind of in between. Perhaps the
confusion is because it is in between the two.
Eleanora
>I have seen this clay listed in some catalogs as a stoneware and others as
>a ball clay. Does anyone know why this is?
>I have been using about 10% in my cone 11 body and the main reason i
>started using it is because i thought it was a stoneware. I already use old
>hickory #5 for my ball clay for it's whiteness and refractoryness (sp?).
>But if foundry hill is just another type of ball clay i could probably
>eliminate it to make things simpler.
>Can anyone comment on this?
>thanks,
>Paul
>
>______________________________________________________________________________
>Send postings to clayart@lsv.ceramics.org
>
>You may look at the archives for the list or change your subscription
>settings from http://www.ceramics.org/clayart/
>
>Moderator of the list is Mel Jacobson who may be reached at melpots@pclink.com.
--
Bellows Falls Vermont
www.eleanoraeden.com
Ron Roy on wed 29 nov 06
Hi Paul,
Like many of the clays we can get in North America - FHC seems to me to be
between a true ball clay (high shrinkage) and a stoneware clay - around 12%
overall shrinkage.
The over all shrinkage at cone 8 oxidation is about 14% - I don't have any
data on the Old H #5 so I can't comment on it - you should test both to see
how they compare.
I do know that FHC is a very reliable clay - if you were to replace it with
OH#5 you should be aware of how variable that clay is - I would not advise
eliminating FHC because it is so reliable.
It is also advisable to have a number of different clays in any body -
because it cuts down the chances of any one clay affecting the body badly
when it varies.
RR
>I have seen this clay listed in some catalogs as a stoneware and others as
>a ball clay. Does anyone know why this is?
>I have been using about 10% in my cone 11 body and the main reason i
>started using it is because i thought it was a stoneware. I already use old
>hickory #5 for my ball clay for it's whiteness and refractoryness (sp?).
>But if foundry hill is just another type of ball clay i could probably
>eliminate it to make things simpler.
>Can anyone comment on this?
>thanks,
>Paul
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Paul Borian on thu 30 nov 06
Ron,
In what way does old hickory #5 vary? Do you mean shrinkage, refractoryness
or both? I thought i had heard that is was a fairly stable clay.
Until you made this comment i was actually thinking of cutting out the
foundry hill and just using old hickory, mainly because OH#5 is a little
more refractory and i fire to cone 11.
Now you have me thinking maybe i should do the opposite. I only need about
20% ball clay and it is easier to just stick with one brand.
Could you elaborate a bit on your comment about OH#5?
thanks,
Paul
David Beumee on thu 30 nov 06
Paul wrote:
"> >I have seen this clay listed in some catalogs as a stoneware and others as
> >a ball clay. Does anyone know why this is?
> >I have been using about 10% in my cone 11 body and the main reason i
> >started using it is because i thought it was a stoneware. I already use old
> >hickory #5 for my ball clay for it's whiteness and refractoryness (sp?).
> >But if foundry hill is just another type of ball clay i could probably
> >eliminate it to make things simpler."
Comparing OH #5 and Foundry Hill, now "New" Foundry Hill Creme, both have very good plasticity, very nearly the same shrinkage rate at cone 10, 18 and 17%, and comparable absorption rates at cone 10, 3.6 and 3%. "Not much" cracking or warping for OH#5 at cone 10, and no cracking or warping at all for Foundry Hill. As a ball clay, OH #5 has a very smooth and sticky feel of course, and Foundry Hill also has fine texture, but without the slick and sticky feel of a ball clay. For fired color, OH #5 fires to a very light color, and Foundry Hill fires to a light tan color in reduction at cone 10. The real difference for me is the excellent dense feel of Foundry Hill, like a clay that begs to be used in a throwing body, and this is why I have until now considered it a stoneware clay, even though it is usually listed a ball clay. Using Foundry Hill in a stoneware body mixture is an excellent way to get the body to "stand up" to repeated working on the wheel.
From my growing experience with Plainsman clays from Canada, including a fine plastic stoneware clay called Palestone, I now understand that the definition of a stoneware clay is one that naturally contains feldspar and silica in such a balance that it (almost) can be used as a vitreous stoneware body with no additions.
David Beumee
Porcelain by David Beumee
Lafayette, CO
-------------- Original message ----------------------
From: Eleanora Eden
> Hi Paul,
>
> I have had this question myself. Digitalfire website categorizes it as a
> stoneware.
> If memory serves, some of clayart's experts call it a ball clay. I did test
> bars of all
> of my clay materials to ^3 which is where I am going with it, and it seems to be
> in the middle somewhere at this temp. So I call it kind of in between. Perhaps
> the
> confusion is because it is in between the two.
>
> Eleanora
>
>
> >I have seen this clay listed in some catalogs as a stoneware and others as
> >a ball clay. Does anyone know why this is?
> >I have been using about 10% in my cone 11 body and the main reason i
> >started using it is because i thought it was a stoneware. I already use old
> >hickory #5 for my ball clay for it's whiteness and refractoryness (sp?).
> >But if foundry hill is just another type of ball clay i could probably
> >eliminate it to make things simpler.
> >Can anyone comment on this?
> >thanks,
> >Paul
> >
> >______________________________________________________________________________
> >Send postings to clayart@lsv.ceramics.org
> >
> >You may look at the archives for the list or change your subscription
> >settings from http://www.ceramics.org/clayart/
> >
> >Moderator of the list is Mel Jacobson who may be reached at melpots@pclink.com.
>
>
> --
> Bellows Falls Vermont
> www.eleanoraeden.com
>
> ______________________________________________________________________________
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at melpots@pclink.com.
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