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Isculpt

Member Since 03 Apr 2010
Offline Last Active Today, 02:02 AM
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#67435 Help! Hand-Dug Clay Needs Additive For Strength

Posted by Isculpt on 07 October 2014 - 08:39 PM

Dandasana! a powerful  pose. Try it Jane sitting on a firm cushion, stting bones right on the front edge of the cushion, you'lll be there in no time. Right in the moment. I can see you making those beautiful canoes for Bear! :)

Babs, Given that I have two very curious and large dogs who share my studio, I suspect that the Dandasana pose may do wonders for me but not for my production schedule!  I can just imagine the broken sculptures that would result from working at dog-level! 

Jayne




#67376 Help! Hand-Dug Clay Needs Additive For Strength

Posted by Isculpt on 07 October 2014 - 04:08 AM

Lou, the clay is dug from what I suppose you would call river bottoms.  Before there were vehicles, the Indians paddled canoes across the river to this patch of land to collect clay.  (The clay was so desirable that the North Carolina Cherokee would travel - sometimes on foot - to South Carolina to acquire this clay from the Catawbas.) This clay is used to make small bowls, peace pipes, etc. But to make larger bowls, clay from a different area had to be added in at the proportion of 1 part strengthening clay ("pan clay") to 4 parts river bottom clay ("blue clay").  That clay could be found in many places.  The clays, full of debris and rocks, are spread to dry in the sun, after which the debris and rocks are removed by filtering through a window screen. (Before there were screens, it was simply picked out by hand.)  Then the clay is covered with water until it has become a smooth slip.  That slip is poured into a pillow case or onto a cloth covered surface and allowed to dry to workable consistency.  It is wedged and formed into coils.  The process is unscientific, with the quality of the clay judged by feel, with one generation teaching the next generation.  If you look at the earlier posted photo of Bill handing clay up to his grandmother, clumps of rejected clay are scattered around her feet.

 

Traditionally, the clay has been strong enough to withstand a punishing firing system. After preheating pots next to a fire or in a fireplace (or for the last half century, in an oven), the pots are placed in the hot coals of a fire that has burned down.  Then another fire is built over the pots with small pieces of wood.  As that fire burns down, layers of pine bark strips are laid over the pots to smother the fire and create the characteristic shiny black and grey areas.  This firing takes place on the ground or in a very shallow concavity, a method that is risky to the pot and to the potter.  In fact, a tribal elder recently lost her home to a fire that spread when she was burning pots.  

 

Catawba pottery is not as widely known as many western tribes' pottery, but Bill's grandmother Georgia Harris had a one-woman show at the Renwick and is the only person to have been posthumously awarded the Folk Heritage Award by the NEA.  In their press release in 1997, they wrote about Catawba pottery:

      In the western United States, many Indian pottery traditions thrive and enjoy wide recognition.  In the east, however, few Indian pottery traditions survive, and only one - that of the Catawba of South Carolina - maintain a direct connection to the pre-conquest past. "The Catawba potters constitute the only group of potters east of the Mississippi River which has maintained this aboriginal art form in a nearly pure state from pre-Columbian times to the present" according to Catawba historian and culture scholar Dr. Thomas J.Blumer. 

 

So, no, there is no QC or use of witness cones or anything more nontraditional than using an oven to preheat the pots.   I hope this answered your questions?

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#67332 How To Complete A Mistake? Please Help

Posted by Isculpt on 06 October 2014 - 11:41 AM

You say that you hollowed it out as best you could; how thick is the thickest area?  I'm a sculptor too, and I'm not terribly particular about getting all the walls to be the same thickness, but I do try to keep things under 1/2".  I would suggest that you preheat the piece for a long time if it hasn't been drying for more than a few weeks.  I prefer to play it safe and preheat regardless of how long the piece has been drying.  The alternative to losing a few bucks on electricity could be losing a sculpture that took you days to make,  To me, there's no question which way I'm going on that decision.  I've tried firing without a long preheat and with a long preheat, and I can tell you that it makes a huge difference.  I never lose sculptures if I preheat, but I've lost week's worth of work allowing someone else to bisque it without preheating. Because it uses so little electricity, I usually preheat for about 12 hours under 200 degrees.  Then I go with a slow bisque.  There are posts on here regarding suggestions for a slow bisque schedule.  

Jayne




#67275 Help! Hand-Dug Clay Needs Additive For Strength

Posted by Isculpt on 05 October 2014 - 10:14 AM

My husband recently dug clay from a clay hole that his tribe has used for years, and the clay vein was so smooth that the clay peeled off the walls of the clay hole.  He and other tribal members thought they'd found the best clay yet from that spot.  It's now been dried, screened, soaked and dried to workable consistency. It wedged up beautifully but they find that the clay has no strength!  A coil-built pot sags under its own early weight.  

 

His thought is to return to the clay hole and dig what he would consider poor clay, process it, and add it in.  But I wonder if anyone has a suggestion about an additive that would add significant strength without drastically changing the color of the clay, which is a deep brownish- grey color, which fires to a tan or yellow-brown.  This clay is slightly darker and more grey than the clay that is usually acquired from the hole, making us wonder what is missing.  The pots will be burnished, preheated to 500 degrees and fired on the ground in the traditional way. Any help is greatly appreciated, since the clay hole is inaccessible during hunting season, which has begun.  I've attached an image of a fired pot.  

 

Thanks, Jayne 

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#63441 Help Me Decide What To Do About A Cracked Kiln Lid

Posted by Isculpt on 28 July 2014 - 08:40 PM

When I purchased a large top-loading Olympic kiln last summer, it arrived with a crack in the lid where the handle's screw had been run in, apparently without pre-drilling.  The crack didn't go all the way through, and I was promised a new kiln lid if I would accept delivery of the kiln.  The lid has one of those hinges that goes all the way down the back of the kiln, which I am told is not easy to replace.  Before delivering the kiln, the merchant from whom I bought it repaired the crack with kiln mortar. It has been 8 months and the crack has not re-appeared.  I know the seller is hoping I'll forget about it, and truthfully, I'd like to.  I fear that things may go from (not-too) bad to worse if the lid is replaced.  Given that the crack hasn't reappeared, should I feel relatively confident that it won't?  Or am I being foolish not to replace it?

 

UPDATE:  I received a call from Bob Haugen, president of Olympic Kilns.  The delay of 8 months was not of his doing - or not doing, a fact I was well aware of.  He has promised to deliver and install the new kiln lid himself.  You can't ask for better than that. Thanks again to all of you who advised me to have it replaced.




#63373 What Are You Working On?

Posted by Isculpt on 27 July 2014 - 10:52 PM

Wow, Pres, those wedding jars are fabulous. I hope neither couple ever gets divorced because there's gonna be a nasty custody battle!  Seriously, a wedding gift that wonderful is well worth the wait, as I'm sure your friends would agree.

 

And thanks, Rebel, yeah it's really a teapot. The head and chest of the farthest girl lifts off so water can be poured in..  I love your your carved piece and the one with flames too. It made me want to create something with flames! When I was a wood carver, I made a wall piece with an angel hanging upside down over flames. The first time I took it to a show, a woman stood just outside my booth and yelled "blasphemy".  I pointed out that just above the flames was a spigot and holy font in case the flames got too high. She was not amused.




#63275 What Are You Working On?

Posted by Isculpt on 26 July 2014 - 01:07 AM

Oh, and back on point, I'm working on a teapot that sold 3 years ago at a teapot show.  A customer of the gallery that sold it requested I reproduce it, more or less. As I work on it, I wonder how the heck I made it the first time!  It was 3 years ago and I had just started in clay and I knew even less than I know now.  It's a pain in the a** and I'll be glad to finish it....if I ever do. 

 

Also, I'm working on a tile that keeps breaking...and it's not even dry yet. I've put it back together with paperclay twice.  It looks like this one is going to hold....I hope.  It's for a young  friend who is nearly finished with chemo for ovarian cancer.  It HAS to be ready and in one piece so that I can hand it to her when they remove the IV for the last time on the 5th of August!  IT SIMPLY HAS TO !!!! 

 

Jayne

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#63274 What Are You Working On?

Posted by Isculpt on 26 July 2014 - 12:38 AM

Stellaria, I'm still so freaked out about the echidna with the four-headed um, boy parts, that I'll have to work my way up to the octopus and the sea pig.....

Jayne




#63228 What Are You Working On?

Posted by Isculpt on 24 July 2014 - 10:10 PM

This has gotten way off point, but out of curiosity I just Googled 'echidna' and found a bizarre you tube video entitled True Facts About baby Echidnas" that starts "The echidna was created 54 seconds after God created marijuana..."

 

Oh my, the things I have learned reading the ceramic Arts Daily Forum!!!!




#62685 What Can I Make Besides Food-Holding Stuff?

Posted by Isculpt on 18 July 2014 - 02:50 AM

lidded boxes

frames

tiles

simple animals & birds as decorative ornaments

jewelry pendants

business card holders, desk accessories

nonfunctional decorative teapots

small reliquaries to hold written prayers/thoughts

lamp bases

wall-hung decorative platters

 

Visit Pinterest for a zillion ideas.  I have created a board of functional and non-functional pieces that I've found online that appeal to me at http://www.pinterest...nal-decorative/.  There are many other boards on Pinterest with many other ideas. 

 

Jayne




#62312 Image Envy ...

Posted by Isculpt on 12 July 2014 - 09:44 PM

Chris, you perfectly expressed the "artist's angst" that is the downside of today's easy access to the work of so many others. 

 

As I wrote the word "angst", I wondered if that was too melodramatic a word for the way most of us feel when we look at the work of talented other folks.  So I looked up the precise definition and found:  "Angst is a transcendent emotion in that it combines the unbearable anguish of life with the hopes of overcoming this seemingly impossible situation". 

 

Yup, that about covers it!




#61487 Real Time Preheating Question

Posted by Isculpt on 28 June 2014 - 08:36 PM

Oldlady, as you can see, neither of the dark washes was obscured by the acrylics, although the Mayco wash is definitely more assertive than the copper carbonate.  Copper carbonate used this way is a little unpredictable, but I have added more cc to the water and gotten a darker effect, although not as dark as the Mayco "Stoneware Wash".  On the other hand, the Mayco "Stoneware Wash" may give a lighter effect if greatly diluted.  Time for more experiments!

.

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#61263 How To Strengthen Delicate Ceramic Parts After Firing

Posted by Isculpt on 22 June 2014 - 12:47 AM

Thank you all for a mind boggling array of ideas.  As for you, Babs, I can assure you that I do indeed have lots of problems.....and some of them are even ceramics related! ;) 

 

Jayne




#61142 How Do You Run Clay Through Your Slab Roller?

Posted by Isculpt on 18 June 2014 - 11:31 PM

Wow, that's a wide range of ideas for ways to handle this challenge.  I'm gonna try several to find the one that easiest/best for me.  I don't quite understand the diagonal cut that Mark mentions, but I'd like to.....

 

In answer to Mark's question about why I'm cutting the block into thin slabs, I had a problem last year (and posted about it here) wherein my 30" wide roller table (two cabinets joined together, 72" long overall) began to wriggle apart just enough that the canvas was getting sucked down into the crack between them when I tried to roll canvas and clay through the roller.  I took it all apart and reassembled the two cabinets with much stronger joins between them.

 

Since then I've had no trouble with the tables being pushed apart from the pressure of the slab roller, but I'm afraid that if I send too big a chunk of clay though, it might force the cabinet bases apart again. In the image attached, I'm showing the 25-lb block of clay that i get from Highwater Clay.  Surely no one is suggesting that I try to force that big modacker through those rollers?  How thick a slab should I feel comfortable forcing through my slab roller?

 

Attached is an image of the cabinets as a slabroller table...And yes, I've been told that no serious clay studio uses expensive cherry cabinets for storage, but I was building my studio just as the housing bubble burst 3 years ago. That bust cost me my construction job, but it gave me a studio full of functional and beautiful solid cherry cabinets ... for cheap!!  BTW, that's Mr. Evans and Mrs. Jones bookending the slabroller.....

 

Jayne

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#60089 White Spots On Bisque-Fired Brown Clay

Posted by Isculpt on 05 June 2014 - 08:54 PM

Thanks, Roberta, for the compliment.  My mentor taught me that there is no such thing as a ruined sculpture and I have taken that as a challenge, devising lots of ways to fix my mistakes! 

 

Tenyoh, the reason that the woman holding the bird has such a matte finish is that I used a wet sea sponge and when the piece was leather hard, dabbed her face, neck and hands so that it had a velvet-like "nap" to the surface.  I've only used that technique once, but I really liked the effect.  It's nearly impossible to do on a small, detailed sculpture, though. That piece wasn't large (maybe 12"), but it didn't have lots of nooks and crannies to try to get the sponge into.  Using watery washes works best on a piece that hasn't been fired to vitrification. 

 

I have hard water, but I have a salt-based water-softener unit, which may have something to do with the white spots.  It seems somewhat logical that applying water softened with salt could cause a similar effect to "scumming".  I wonder ......

 

jayne