QotW: Do you synthesize, formulate or modify the clay bodies for your use?

[Pres]

Hi folks, no new questions posed in the pool, so I will pose one that has been often asked around in the way of advice on the forum.

Lately I have seen more interest in manipulating clay bodies or natural clays with additives and such. Some people have manipulated the clay bodies purchased with sand, and others use vinegar and other things to expand the plasticity of the clay body. 

QotW: Do you synthesize, formulate  or modify the clay bodies for your use?

I will have to say that I do very little with clay bodies happily buying clays that I have tested from my local (100 mi) Standard Ceramics. I have added grog to clay for throwing purposes, some granular manganese in some clays for speckling as I did with iron shavings, copper shavings and  and granular rutile. I also would improve my slop clay with the addition of a1/2 cup of vinegar to one gallon of water for use when pugging and it would help after a week of storage.

I am not comfy with mixing clays, as I did some in college for the courses, and found the dust and the mask and hoods and such pretty confining, along with the use of the Soldner tub type  clay mixer combined with final pass through the Walker Pug mill with all of the safeties removed.

best,

Pres 

[glazenerd]

It has been close to a decade since I bought any commercial clay. Years ago, I put the same crystalline glaze on five different commercial porcelain bodies, and got five different results. That single incident sparked my curiosity about clay formulation; which turned into an obsession for awhile. I do crystalline tile almost exclusively; and every commercial porcelain body I tried- warped. From that, I developed a crystalline body that actually promotes crystalline growth; instead of hindering it. I developed a porcelain tile body that I roll out on 2 x4 x 1/2" luan, and let it sit until it pops off on its own. My days of flipping, weighting, and spending hours trying to prevent warping are long over. Few years back I developed an extensive line of colored porcelain: which I use from time to time. Local supplier wanted me to distribute it; but not really had the time to get that involved. A shoulder injury from a few years back has also hindered that endeavor.

My bigger interest of late has been collecting and processing locally sourced clay. It holds my interest; breaking it down and figuring out how to make it a workable body. I have samples sent to me from across the US, and on rare occasion- other countries. Rather fascinating to see the results from iron disulfide, hematite, and magnetite samples. Still toying with the idea of bringing back a semi-load of hematite clay from NE Oklahoma- best looking cone 6 results I have ever seen. I have been contacted by potters across the globe for in depth discussions on how to fix their naturally sourced clay issues. The most complicated puzzle was sub-tropical laterite from India; took awhile to find the solution. (43% total iron/alumina content). Collecting and processing natural clay is more popular than most realize; but it is not a topic that is widely discussed here.

A few months back another interest has taken center stage in my life: so clay may have to take a back seat for awhile.

Nerd -- the pic below is Oklahoma hematite.

[JohnnyK]

I've tried making paper clay in very small amount to try using for patching but was not impressed...I did have a customer who wanted me to incorporate his parent's ashes into the surface of an urn he wanted me to make for him. This was the result:

[Kelly in AK]

I use a commercial cone 6 body for soda firing and one that’s “wild,” fired at cone 03.

That one needs a plasticizer (I use 1-1/2% Veegum) and takes a lot of effort to make it usable. I’ve used it for about five years. In the first year I got a lot of information through testing, but I still have a lot to learn. 

[glazenerd]

and by the way: like glaze- plenty of failed recipes as well.

Tom

[glazenerd]

Oklahoma "wild" hematite clay at cone 6- unglazed.