Storing clay

in article ObfQb.5659$ snipped-for-privacy@bgtnsc04-news.ops.worldnet.att.net, CNB at snipped-for-privacy@hotmail.com wrote on 1/23/04 2:09 PM:

The sculpture studio at the Evanston Art center (near Chicago) uses the garbage can technique with a damp cloth on the top. It seems to work, but the clay is pretty stinky. I generally brought my own terracotta, but other people seemed to be able to dig into the cans easily enough and got good results.

Marty

In article , Marty Kenny writes

Stinky clay is good! I know this sounds a bit odd, but plasticity is improved by keeping; it allows the growth of organic matter in the clay which is like a good Gardener's Compost Heap, its growth and decay acts as a lubricant, so you need less water to work the clay and it

*stretches* further.

Does that also increase the shrinkage percentage?

I wonder if this depends as much on local humidity as the degree of seal on the plastic bags. I kept 25# of clay in its original heavy plastic bag nearly untouched for 14 years. Every few years I'd think to check it, and toss in a little water. Finally started using it last year and it was just fine. The key thing might be that it was in my basement where it is on the humid side, which may have slowed drying. The plastic bag was simply folded over inside its box, no special seal.

Bob Masta dqatechATdaqartaDOTcom D A Q A R T A Data AcQuisition And Real-Time Analysis

This is exactly why I'm asking the question. I used some clay that I had been saving a while that was from my throwing bucket. I had removed the extra water and had it at least six months in a bag. It finally dried enough to use. Smelled like rotten mud but oh mad how nice it was to throw. I noticed that it was more moist than the clay that I had been taking out of my bags and decided that my clay wasn't staying wet enough. I want to keep it wet enough so that it can age. I listened to a tape how George Ohr (famous potter born in Louisiana, worked in Louisiana and Mississippi) had kept his clay in a vat outside completely immersed in water for a year before he would use it and I think a lot of you know his results.

I noticed that some of the bags were not tied well but most were. It is very humid in my area but I keep my clay inside. It would probably be better if I kept it outside. I went through several bags yesterday and they are to hard to work with. No wonder my wrists hurt.

oops. Excuse me. Ohr was born in Mississippi. I believe I got that wrong.

Question: What does light freezing do to water saturated clay? Been building up a bucket of remainder clay, pouring off the excess water down to about an inch and leaving the concoction outside hoping the weak sun and desert dryness would evaporate more moisture so I could begin to reclaim the material. We had an unusually cold night and the top 1/8 inch was frosted to frozen. The condition didn't last very long once the sun got up, but... Will all those wonderful bacteria be dead? Kathy

I don't know what the freezing can do but I can tell you a good way to get the extra water out of the clay. I made a canvas bag to dump the clay in, tied the top with a rope, then hung it outside. It removes water quicker than leaving it in the bucket. It also keeps out the extra stuff that can fly in there. I would protect it from freeze though. I think the clay is still good but lets see what someone with more experience says. Crystal

Pete Pinnell commented at a workshop I was at that often times when clay gets harder as the bag sits it's not because moisture is being lost from the bag, it's because the clay particles weren't really fully hydrated when the clay was mixed. Most commercial clays are made by adding water to the dry ingredients until a workable consistancy is achieved. The problem with this is that it the clay particles are not fully hydrated and absorb more water over time, hence the clay gets stiffer. Clay that is made by making it into a slurry and then dried out to a workable consistancy doesn't have this problem.

deg

hmmm..... That's interesting. I ended up taking a plastic bin out yesterday and put about 50 lbs of clay in it. I covered it with a terry cloth as was suggested and pored water over it. A couple hours ago I used some and it's great. Threw great. Thanks, Crystal

In article , Lindsay MacArthur writes

No!

Steve Bath UK

That was common practice in all the old country potteries here in the UK; they always made clay this year for next year's use.

Steve Bath UK

In article , CNB writes

In article , Kathryn & Stuart Fields writes

You would only lose some of them if the whole lot froze solid. What freezing does is to separate the clay and water temporarily. Some clays re-absorb water quickly some don't. Going back to traditional clay preparation techniques; it was also the norm to dig clay from the pit in the autumn (fall) and leave it out to over-winter when freezing would break it down and make it easier to turn into slurry in the spring. Then it was wet-mixed and then run out into drying pans before wedging it and storing it to sour, ready for next year.

Steve Bath UK

In one of my answers for potters books it discusses this issue. Although I can't think of the exact title, it is a small paperback based on questions and answers used in Ceramics Monthly. The writer suggests taking a manmade sponge, wet it, and then place it in the bag on top of the moist clay. You then seal the bag tightly and then place it into another bag upside down so the openings are at different ends of the clay. The author states this will keep your clay moist for years. Natural fibers will rot. I keep my clay in a non-working fridge. I have clay that is 2 years old and still workable even though I have not placed the sponge in it. If the clay gets too dry in the bag, place it in the freezer overnight. After you take it out and let it thaw, you will be surprised how much more moisture has been "added" to the clay. Steve in Tampa, FL

Steve and all That is an excellent suggestion. I managed to score a smaller chest freezer (doesn't work, but who cares) and use it to store my clay. Can't beat free. I found an old couch cushion. Removed the cover, wet the foam, and placed it like a blanket on top of the clay in the freezer. Keeps everything ready to use. BTW, a 7 cubic foot freezer will hold

700 pounds of clay with no trouble. You can even use an old refrigerator, if you have the room. Lay it on it's back, doors UP. Just remember to put a lock or hasp of some sort on it, so critters and small kids can't get in. Pulling frogs and lizards out gets old real fast. Wayne Seidl Key West FL

Well, those are two good and interesting comments. I shall try the hanging bag and won't worry about the freezing--probably won't happen much more this year any way. Also, the bag will be better than leaving it out where the multitude of animals in our desert would help lower the water without good results to their systems.

Thinking about the bag trick in our area brings out an interesting potential problem--bees. Because of the extreme lack of standing or surface water, any time some is available, one finds lots of flying critters and usually a whole pot load of bees and wasps--one experience with this situation also suggested that the bees, etc weren't very aggressive, so maybe the result will be good all around. We'll see.

I store most of my clay in the garage on the concrete floor in a dark cool area. It stays workable for ages. If your plastic bags are too porous perhaps an extra plastic bag would do the trick. If my clay has dried out too much, often happens in the studio, especially if the children in my classes don't close the bags well enough :o). I simply slice it into 1 inch thick slabs and dip it in clean water, leave for about 20 minutes then do my wedging before working. The clean water is absorbed very easily and quickly. If you use slip it seals the surface. Annemarie