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#1 MMB

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Posted 21 July 2013 - 10:28 PM

So if a clay is technically a "short clay" does that mean its not structurally as strong as a normal more workable clay. Ive read a bit that some sculptures like a short clay because it is usually heavily grogged and doesnt shrink as quick. The short clay Im dealing with has limitied workability. It will crack when bent on a hard angle but can be easily smoothed afterward. I decided to try and throw it and it threw well (yet I threw it way too wet). I took a rib to it before I cut it off the wheel and it has had no trouble drying.

 

I figured Id speak a little about the situation to add info but Im really just curious if it is an inferior final product. I mean if it were to be thown and the rims compressed, even though it has limited workability off the wheel, is it still a weaker clay in the end?



#2 Mark C.

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Posted 22 July 2013 - 12:03 AM

I think of short clay as not throwing well. That is it will not pull up tall thin forms. As far as structurally I do not think its any less strong when fired to maturity.

If its super heavy with grog or additives than maybe.

My 2 cents.

Mark


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#3 Marcia Selsor

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Posted 22 July 2013 - 06:13 AM

I agree with mark about the throwing aspect of short clay. It can also be frustrating for handbuilding. To test for "plasticity" opposite of shortness, roll a coil and bend it. If it easily breaks before bending around, it is short.

 

Marcia



#4 minspargal

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Posted 22 July 2013 - 07:27 AM

Short clay is hard to  throw and hand build. I tried some new clay last year that was short and i ended up making tiles with it. It was a lovely brown color and i had had visions of making fat dogs. Ended up making tile coasters and i will say some of the low fire glazes had some neat effects on that warm brown clay.



#5 OffCenter

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Posted 22 July 2013 - 08:06 AM

Short clay just refers to the lack of plasticity in the clay and has nothing to do with the fired strength. BUT, grog does affect fired strength. A little grog doesn't make enough difference to worry about but a lot of grog does make the fired piece weaker even though it is probably still strong enough for most purposes.

 

Jim


E pur si muove.

"But it does move," said Galileo under his breath.

#6 Benzine

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Posted 22 July 2013 - 09:06 AM

So, that's what people mean, when they say a clay "Has no legs"?


"Anything worth believing, is worth questioning"

#7 oldlady

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Posted 22 July 2013 - 09:45 AM

wine drinkers talk about legs.  never heard of the term with clay.


"putting you down does not raise me up."

#8 Pompots

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Posted 23 July 2013 - 12:36 AM

So, what is the main use of the "short caly"?  if it is not good for throwing and hard for hand building, what is it for?



#9 OffCenter

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Posted 23 July 2013 - 07:22 AM

So, what is the main use of the "short caly"?  if it is not good for throwing and hard for hand building, what is it for?

 

I don't think anyone deliberately acquires short clay. It is just something you run into sometimes for various reasons and need to correct by not buying or mixing that clay again or by fixing it. My pugmill cuts my clay's legs off above the knees.

 

Jim


E pur si muove.

"But it does move," said Galileo under his breath.

#10 Idaho Potter

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Posted 24 July 2013 - 05:54 PM

How would you know, Jim, you don't use your pugmill.

 

Shirley



#11 MMB

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Posted 24 July 2013 - 11:30 PM

Well I wanted to get back to this but have been out of town. My clay is without grog. I was stating the idea of adding grog from a certain sculpters point of view, which is entirely not my interest. Like Ive said it cracks when coiled and curled so obviously the plasticity is aweful. My misunderstanding was that it cracking and breaking was because it was "short clay" this being read from The Potters Dictionary. Maybe I misread it. But really that discussion is besides the point. My main focus was on structural integrity after it is fired. Its proven, so far in smaller amounts, to throw decently. If I continue to experiement with it and it continues to be usable, as long as I take the necessary steps to compress the rim and what not could it be a weaker body once transformed to from clay to ceramic.

 

Anyone ever use Loafers Glory from High Water? My clay has a little less porcelain like texture and is slightly more tempermental. Just to give and example.



#12 JBaymore

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Posted 24 July 2013 - 11:36 PM

Short clay is great for making "wabi sabi" chawan. :D

 

 

best,

 

............john


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#13 Marcia Selsor

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Posted 25 July 2013 - 07:13 AM

sometimes you need to just let freshly mixed clay sit for 2 weeks. I had a white clay like that. AFter 2 weeks is was fine. Short clay could use more ball clay in the recipe, maybe more aging, maybe 6-8 drops on the concrete floor, depends on many things.

Marcia

#14 Benzine

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Posted 25 July 2013 - 08:10 AM

Short clay is great for making "wabi sabi" chawan. :D
 
 
best,
 
............john


Ha, of course you would say that.
"Anything worth believing, is worth questioning"

#15 oldlady

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Posted 25 July 2013 - 08:36 PM

contact highwater in asheville and ask for a technician familiar with loafers glory.  i use little loafers which is cone 6 and love it.  if your clay doesn' t work, nothing does,  it might be time for a change.


"putting you down does not raise me up."

#16 TJR

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Posted 25 July 2013 - 11:02 PM

You know, I was going to say to add ball clay, but Marsia already beat me to it. I'd ask her to marry me, if I wasn't already married. She probably has her own can of WD40 as well.

T.






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