Eleanora Eden on tue 29 aug 06
Hi all,
Well, for the name alone it is worth investigating black charm ball clay.
The specs say it is way up on the absorption compared to OM#4 but
way, way down on the shrinkage. Also slightly less refractory.
Any experience with this material? Laguna lists it in its catalog.
Thanks in advance,
Eleanora
--
Bellows Falls Vermont
www.eleanoraeden.com
Ron Roy on wed 30 aug 06
Hello again Eleanora,
I just found a data sheet on black charm (a Spinks clay) - it does not look
that different from Spinks FHC except they say the raw colour is black -
and there is only a little more iron than in FHC - so I have to summarize
that there is a lot of carbon in it.
Best to get an answer from Spinks re the carbon content. If there is a lot
- that can be problematic in firing - but carbon is a great plasticizer -
so some is OK but - depending on how you fire - and how much iron is in the
clay - it could be a problem.
I would say a little (5%) could be OK but a lot might be a problem -
besides - who uses it? - and do they expect to keep stocking it?
If Laguna is using it in a clay body then sales of that body might
influence availability.
Some things to think about - let me know what Spinks says about carbon
content please - RR
>Well, for the name alone it is worth investigating black charm ball clay.
>The specs say it is way up on the absorption compared to OM#4 but
>way, way down on the shrinkage. Also slightly less refractory.
>
>Any experience with this material? Laguna lists it in its catalog.
>
>Thanks in advance,
>
>Eleanora
>--
>Bellows Falls Vermont
>www.eleanoraeden.com
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Eleanora Eden on thu 31 aug 06
Hi Ron,
Yes, your assumptions are correct according to Jon Pacini at Laguna,
he said "--- lots of organics --very plastic".
Your post reminded me that I already had a post in to Spinks about C&C
ball clay for specs and they have not answered so I have re-sent it with
an additional request also about Black Charm.
I had just re-read an old post from Jonathan Kaplan who said the same
thing about having a good variety of clays in the body and that put me on
my current quest to add to my collection.
I already have bought their FHC. I made up a test bar of it and
it seemed exceptionally sticky and dark. I haven't been clear on FHC's
category since one listing I see calls it stoneware. Sure felt like ball clay.
Thanks again,
Eleanora
>Hello again Eleanora,
>
>I just found a data sheet on black charm (a Spinks clay) - it does not look
>that different from Spinks FHC except they say the raw colour is black -
>and there is only a little more iron than in FHC - so I have to summarize
>that there is a lot of carbon in it.
>
>Best to get an answer from Spinks re the carbon content. If there is a lot
>- that can be problematic in firing - but carbon is a great plasticizer -
>so some is OK but - depending on how you fire - and how much iron is in the
>clay - it could be a problem.
>
>I would say a little (5%) could be OK but a lot might be a problem -
>besides - who uses it? - and do they expect to keep stocking it?
>
>If Laguna is using it in a clay body then sales of that body might
>influence availability.
>
>Some things to think about - let me know what Spinks says about carbon
>content please - RR
>
>
>>Well, for the name alone it is worth investigating black charm ball clay.
>>The specs say it is way up on the absorption compared to OM#4 but
>>way, way down on the shrinkage. Also slightly less refractory.
>>
>>Any experience with this material? Laguna lists it in its catalog.
>>
>>Thanks in advance,
>>
>>Eleanora
>>--
>>Bellows Falls Vermont
>>www.eleanoraeden.com
>
>Ron Roy
>RR#4
>15084 Little Lake Road
>Brighton, Ontario
>Canada
>K0K 1H0
>
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--
Bellows Falls Vermont
www.eleanoraeden.com
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