[Why my clay acts like this?]

2 hours ago, Kelly in AK said:

Tina! You just made my day.

: ) Thank you sooooo much! kisses! ; )

[Why my clay acts like this?]

Hi all! 

Some updates... I finally built and cooked my first pot! : ) well... it's a vase I guess. I don't know if it has cooked thoroughly or not, but it turn from slightly greenish gray to pinkish beige. A few small areas had a different , more saturated green hue when I took it out of my kiln. It's hard on surface, not scratches with fingernails but does with sharp metals. Absorbs water but doesn’t disolve or making my finger muddy when rubbing it wet. Still I'm afraid to fill it with water although some smaller thinner testing items I cooked with it are still  holding strong  under water after 20 days.

hunting/making clay is still in progress. as the last formula didn't work (infact it couldn't be tested as it had a horrible smell, something like fetid swamp rotten eggs after 5 days). Most likely because my bentonite keeps molding, no matter how many times I remove the mold layer from the top. So I finally mixed all the different clays I had and still working on dry powders to find a solution. 

[Why my clay acts like this?]

On 11/16/2022 at 4:06 PM, PeterH said:

Obviously 24-36 ml/2g = 60-90 ml/5g, and note (presumably active) dispersion of 0.1g increments.

 

PS Should you try this --  and it gives an acceptable result -- maybe your bentonite is just extra difficult to wet. In which case using pre-slaked bentonite could be important helpful when making additions to your clay.

Hi! and thank you for these details! 

Now unfortunately I can't do it with such a precision, (in 0.1 of grams). But for sure I will keep trying! Now about 72 hours most of it has settled and there seems no more activity, and also the top layer seems totally dry (even though the lid was on it the whole time). so I will remove that.

 

11 hours ago, Babs said:

I want a really mixed hydrated clay body so I would  add lots more and give it the time it requires to get there. The moulds could be plasticisers!@

Be careful not to throw out the baby with the bathwater.

Next batch of clay will be different.

Hi! and thank you for your response!

Yes, the next batch will be different hopefully the one I'm looking for! perhaps I should've listened to @Min also and try to make something with ready-made clay, but I have this bad habit of trying to understand everything at once and doing all the work myself, from hunting to glazing. I will continue anyway! 

So again thank you and thanks to all who share their experiences. It's a huge help for me and I highly appreciate it! 

[Why my clay acts like this?]

13 hours ago, Babs said:

Sue had a BUCKET, I didn't read closely but as Benton. additions are usually 1 to 2% by weight, which could mean a very light sprinkling over the surface.

With a mix , your last sample good to go. A Slake of 24hrs not uncommon.

Thank you! If you watch the video on that page, the nature of the whole process seems different.  it just submerged after a couple of minutes and was crumbling under water to fully disperse (in 5 hours she says). but mine didn't sink until after 18 hours and it was still a clumpy. then it raised to top again. 

The 5 grams in 100ml I used was derived from@glazenerd formula, which originally was 5g to 220g of clay and 75ml of water.

By the last sample if you mean the last two photos (after 24h) I was hoping that it should have dispersed and sunk completely (vs 5 hours). Perhaps the container wasn't large enough as you said or my bento isn't really bento.

 

7 hours ago, Kelly in AK said:

A thin dusting might settle right away, but any more than that you’ll have a pile of dry material on top of a layer of impervious wet gel. I’m not sure what the scum on top after it all settled is.

Hi! : - * Thank you! 

Yes, a thin layer settled as it's visible in the first photo. I also doubt about it, if it submerged totally (at 16 hours) why again some of it rise to the surface? as you're not sure what that "scum" is, and I wasn't either, so I asked that if I should dump those perhaps using a spoon in my previous post. 

Now after about 36 hours it seems a  little of that top layer (about 1/3) has settled and slightly smells molding (but no visible evidences yet).

Again, Thank you both for your help and care. 

 

p.s. As many times mentioned in this thread that bento can absorb water 15x  its weight, 5g could absorb 75g, or 75ml water. However what I see is more than 50ml is still free water.

[Why my clay acts like this?]

On 11/14/2022 at 1:21 AM, Babs said:

It does!!!!

Use another container and decant into tube after slaking overnight or till it reaches the state Sue describes.

Many folk have a bentonite "slurry" premixed as Sue McLeod  blogs about sitting near their reclaim bucket or in their glaze mixing area.

Well something is wrong, I did that, as she was stated, tried to  sprinkle bentonite on water and not touch that. Mine is a mix? of only 5 grams bento with 100ml(grams) water. But according to her, after 5~10 min it should disperse and after ~5 hours settled down so clear water on top can be siphoned. Mine didn't go like that:

at T+1 minute:

at T+6 hours:

at T+ 18 hours:

at T+ 24 hours:

should I stop this? It feels like it's going to mold.

[Why my clay acts like this?]

12 hours ago, Babs said:

I'd dip that in water then put in plastic for a while.

sure, but didn't want to change the formula that Tom had calculated with much trouble...

7 hours ago, glazenerd said:

Bentonite can absorb up to 15 times its weight in water. So adding 70 ml does not come as a surprise.

Thank you Tom and sorry again for the troubles, hope you've read my message. I know  that about bento, that makes me think if I add 75ml ~= 75grams water/bs to the mix, all the water will get absorbed by bento (5g x 15 = 75) So what will remain for the clay itself? 

7 hours ago, glazenerd said:

The main thing is to keep records as you go. Be sure to mix clay and bentonite well before adding water. 

I am and hope they stay on this site also, they might be useful for someone else. 

Yes, I  did so, but didn't know have to wear a mask.

7 hours ago, glazenerd said:

from what I see, looks like your in the 75ml range total.

Added 10ml more water as a total of 80ml. flattening it inside ziplock bag hopefully to get into the body.

still it's confusing that bento eats all so no water will mixed with clay even if bento dispersed evenly inside body. or perhaps I'm wrong. 

 

6 hours ago, PeterH said:

I wonder if these ideas could simplify the incorporation of bentonite into the mix

How to Add Bentonite to a Wet Glaze
https://suemcleodceramics.com/how-to-add-bentonite-to-a-wet-glaze/

That was interesting, though I doubt it works! mine will probably just clog the top of the tube! I will try that anyway. 

TYSM all!

[Why my clay acts like this?]

7 hours ago, glazenerd said:

Once you blend into a pliable ball: let it stand 3-5 days before checking plasticity. Plasticity is not automatic: it builds up to a peak over a period of days.

Thank you so much Tom.

I guess the water was a bit low, instead of 60ml I added 70ml but didn't go further as you should've calculated it correctly. 

220g clay + 5g bentonite 

after adding 70ml of water/baking soda solution:

nowhere near pliable. after much wedging kneading compressing, best ball shape:

so put it in a plastic bag and sealed for further diagnosis and remedies .

[Why my clay acts like this?]

@Babs @glazenerd

I conducted a PH test, Don’t know if it's useful or not but hopefully it will as it took 2 days!

I didn't have a fancy test kit so I used a red cabbage : D but tried to be as precise as possible. 

01) The amount used for each test.

Then I added 1/2 tablespoon of following materials, stirred well, then added water to 100ml, let that sink if it was required. 

02) HCl , diluted, strongest I could find.

03) Vinegar 

04) Tomato

05) Colorless soft drink 

06) Water

07) Old red recycled clay 

08) Current clay 

09) Egg 

10) Baking soda (saturated water)

11) Bleach 

So I think:

The new clay is more alkaline than old one but not much, it could be around 7.4 or7.5 ( calculating this value with normalization, if the original indicator be of any PH value,  still best approximation for water is 7 and egg is certainly 7.8) Then it falls between these values. 

 

[Why my clay acts like this?]

28 minutes ago, glazenerd said:

I will measure out and weigh a clay I believe similar to yours. Then weigh out how much bentonite. I will post a ratio: x amount of bentonite for every cup of clay. You can then mix by multiplying that base recipe.

That would be a huge favor!  (discard the old reddish clay as I can't find the exact same one and you already know that it was from a couple of years ago). but for the greenish one I can buy whatever amount I want. 

Also the weird thing regarding the scale is I already tried that before, but those small scales are hard to find,  unfortunately if you ask for them they give a look as if I'm a drug dealer (some even ask for it!). But I will try again for sure!

[Why my clay acts like this?]

19 minutes ago, glazenerd said:

Tina:

One final experiment: take a golf/ ping pong ball size piece of your brown clay. Add just a few drops of water and wedge it it; needs a little more moisture. Then put a "pinch" of baking soda on it; wedge that in. Then add a second pinch of baking soda; then wedge that in. Let it sit about an hour. and do the coil test- wrap it around you finger. That will tell me how much acidity/ and or positive charges (iron and alumina) is effecting plasticity. Once I know that; this weekend I will measure out and weigh a clay I believe similar to yours. Then weigh out how much bentonite. I will post a ratio: x amount of bentonite for every cup of clay. You can then mix by multiplying that base recipe. Unless you have a scale; then life gets easier.

Tom

@glazenerd

Sure Tom, please view the pervious post , You posted this while I was editing that one to add more details.

[Why my clay acts like this?]

10 hours ago, Babs said:

Then it may well help Tina. Test and see

That's weird! quote from the the link:

"Vinegar is also used in clay bodies to increase acidity to improve plasticity. The acid works to neutralize sodium ions (from water, leaching feldspars) that tend to deflocculate the clay. Excessive acid may tend to dissolve more feldspar or nepheline syenite negating the effect."

but @glazenerd told me the opposite. or my recycled clay was too much acidic in the first place, or I have trouble understanding it. 

but a recap:

there were lumps in soaked clay even after a week:

putting it  in a water+baking soda helped to disperse:

thinking the clay was acidic, I assumed that the new clay I've found is also acidic, and after the failure with bentonite, I made another batch from it but I also added 1 tablespoon of baking soda to 700g of clay. It had a  subtle reaction (fuzzing). Now I feel it's very hollow and soft, weighing 650g at a clay consistency. (there was some inevitable losses here and there but not that much).

anyone knows how much it's off scale?

comparing recycled (left) with new+baking soda(right):

but I didn't realized I did a big mistake by adding baking soda soda until I saw the pervious clay:

it's covered with salt.  : ( That's gonna happen to the new bach also. : (

so again I run another test, mixing with dissolved baking soda and vinegar separately. 

with baking soda:

not so strong reaction but still fuzzing. 1/2 tblsp in 1/4 cup water dissolved as much possible. 

with vinegar:

very strong reaction, 1 tblsp vinegar in 1 tblspn water.

So it reacts with both, I dont know what's the PH level!

after settling down it seems baking soda (left) still was more successful to disperse the particles (smooth top):

[Why my clay acts like this?]

2 hours ago, Babs said:

Leave it to slake overnight , try adding a little vinegar, stir then put IN cloth to drain. Then wrap and leave. Wedge next day.  May be different. If this is the clay which you wrapped around your finger, plasticity should not take much bentonite to sort. 

Worth a try. 

Yes it was the same clay.

Vinegar? I think the soil is acidic why adding more vinegar? to settle small particles? 

Well I'm now totally afraid to add even a pinch of bentonite again because it had exactly the reverse effect of what I wanted! perhaps I added too much but still it shouldn't change it so drastically and in opposite direction! 

but since you are experienced I'll try that either!

TYSM for guidance. 

[Why my clay acts like this?]

3 hours ago, Kelly in AK said:

I respect that sentiment. What is available to you may very well dictate what you make. That is the order of history. In my city there is one other person using the local clay in significant quantities. He makes tiles and that’s all. That’s because it’s the only thing he sees the clay is good for. He is no fool, all my life no one has said the clay here is good for anything. I make pots with it that are functional by any standard, but it has taken a few years to achieve. You will not solve this in days or weeks. You will solve it if it is your path. 

Alaska has no ceramic tradition. Georgia does. Avail yourself of it. Our cultures are different, I understand that may be easier said than done. 

I also appreciate your attitude toward fixing the clay issues before considering glazing. You must, however, fire any clay you are messing with. You MUST. It is inextricably linked to producing pottery. A small piece placed inside a container in a kiln poses no risk to anyone else’s work, but will give you a great deal of information. There is no sense in finding clay you can form well but turns into bubbling froth, or remains as weak as greenware, when fired.

Your determination and attention to detail are impressive. I hope you solve this, I hope to see pictures of your pottery someday.

Pioneer Pottery by Michael Cardew is an invaluable resource. There are sections on clay that would be useful for you now. Other parts of the book will be helpful later. Whether you’re buying clay or digging it up, you can at least be more informed on the basics. It is freely available on archive .org if you can access that. 

This was the kindest reply I've ever got! Your heartwarming words are really valuable to me and makes me more willing and active. 

So thank you  to the moon and back! it seems I can't post emojies here but a huge hug and kiss! 

I will certainly check out that book. Again, thank you! @ } ; -

[Why my clay acts like this?]

25 minutes ago, Babs said:

1teaspoon aporox 30gms : 250 gms 12%. Quite a bit, was it mixed with water first?

May need to rest it before wedging if you added the powder of bentonite.

No, I mixed both in dry form then with water. after stirring well pour it on that black fabric to draw excess water and sat overnight. this was the next day result, dry on surface but wet underneath. scrub that from fabric and that was the final result in the video.

Even some ordinary mud is more clay like than that.  couldn't even make a thick coil out of it as it was breaking apart. 

[Why my clay acts like this?]

@glazenerd adding bentonite was totally wrong. I added 1 teaspoon to 250g of clay. 

https://sendvid.com/hb3db3wr

wet but crumbling, couldn't even wedge. wasn't clay anymore. 

[Why my clay acts like this?]

1 hour ago, Min said:

Have you tried your kiln to see how hot it will go or do you have access to a kiln that will fire hotter than 900C?

Not yet, (I haven't build it yet because there was nothing to fire). I don't want to use a kiln that is shared (my pots may break and break others). from YT videos that temperature or a little above shouldn't be hard to reach.

1 hour ago, Min said:

May I also ask if you have glaze materials or commercial lowfire  glazes available to you? 

I've found some sources that I can buy either powdered or ready to use glazes, with some variety of colors, and the one that i like is F38 glaze that is transparent. 

I don't know if I could apply that and have a successful glazing I guess it's in same temperature range. but for now I'm looking to fix the clay, as glazing is another complicated story... and to see if my clay will really bake or I should completely change my path.

unfortunately I don't have many choices ( to say well I need that cone clay, those additives, tools, those glazes and all get delivered to my door).

Thank you for your care and help.

[Why my clay acts like this?]

48 minutes ago, glazenerd said:

Sent an email to a Russian potter, another in the Chech Republic: both collect and process wild clay. Trying to get a handle on what is available in your region.

Tom

No.... I don't want you or anyone else to be in trouble for me, that was a favor thanks, but no need to contact others for me.

Ok now that it's sodium bentonite, it isn't Fullers Earth? should I mix it with clay or not? if so, in how much percent? (either by volume or weight). the volume is easier. 

[Why my clay acts like this?]

8 hours ago, neilestrick said:

I'm not trying to be a downer, but I think your best bet is to contact another potter in the area and see where they get their clay. You could spend a ton of time trying to figure this out and end up not being able to fix it. Most clays are not used alone, but are blended with other clays to achieve the properties you need, and not all clays are good for making pots. The other thing you need to consider is your ability to fire pots. If you can only get to 900C (cone 010), then you're not going to be able to make functional work. Pit firing and other non-functional techniques can make some really great work, though. You really need to be able to get to 1000C in order to use glazes.

Thanks for your suggestions and information. I might do so but since joining this forum and doing some research I now know a lot more. I'm interested in learning so perhaps I'll do both.

but I had no idea that a handful of dirt is so complicated! making wine was certainly easier than this!

[Why my clay acts like this?]

9 hours ago, glazenerd said:

Run the same test using your bentonite: see how it goes.

couldn't run the test (see the pictures above). It was an immediate transform. 

[Why my clay acts like this?]

3 hours ago, PeterH said:

Fuller's earth is any clay material that has the capability to decolorize oil or other liquids without the use of harsh chemical treatment.^[1][2] Fuller's earth typically consists of palygorskite (attapulgite) or bentonite.^[1]

This is so confusing, it means that some bentonite can be Fullers Earth? bentonite has calcium sodium potassium types with extra fine particles and plasticity but FE also contains bentonite, isn't plastic, and has the same metals? 

now I have doubts which one do I have?  is it bentonite or FE? any suggestions how to find out? (except for eating bc digitalfire.com says FE strongly sticks to the tongue).

one table spoon water:

one tablespoon of it inside tube, but water couldn't penetrate more than 3mm so I  shake and stir it:

not disolved, full of lumps, so I dumped it out, still stuck at bottom and dry parts:

what that came out:

is it bentonite or FE  or something else? 

[Why my clay acts like this?]

4 hours ago, glazenerd said:

at 10min. indicates your clay has very little fine particles.  At 1hr.15 min it is completely separated. Your clay is mostly comprised of 2+ micron particles; which is large in the world of clay. It also tells me your clay has no appreciable amounts of sodium, potassium, or calcium.

Thank you a lot, although it was disappointing! 

4 hours ago, glazenerd said:

Fullers Earth: which is fairly common in the Asian markets. Given the temp range you are firing to: Fullers Earth would be more beneficial for many reasons.

Does it have any other name? I can't translate it. Or what does it's made of? and what is the mixing ratio? 

4 hours ago, glazenerd said:

Much easier for North American, European, and Australian potters to fix things because we have easy access to many different materials. There are many areas that availability is limited: if any exist at all.

Absolutely! and unfortunate for me.

[Why my clay acts like this?]

On 11/3/2022 at 2:03 AM, glazenerd said:

the left has completely separated between material and water. The right has separated into three layers; each layer being (large particles on bottom, medium particles center, and fine particles on top (looks like colored water).

@glazenerd Regarding that clay, it is certainly acidic but doesn't have wide psd. I took this photo again today, 5 minutes after stirring both:

as you can see there's no gradient anymore as in the last week photo:

It had caused by the reaction of acids and baking soda which release CO2 gas and those gas bubbles prevent the particles to settle down. 

Upon stirring them again today, I found that again some lumps had been formed in the water-only container but not in the right one. Should I try this (look for lumps) with the new one? I already have that in water for the psd test . Or any clay may form lumps staying under water?

[Why my clay acts like this?]

55 minutes ago, glazenerd said:

Tina:

When deciding what to add or remove in a clay body; it comes down to application and firing technique. 1. Functional or non-functional. Functional has specific limits, non-functional has none. 2. Firing- pit, kiln, raku: different firing techniques create their own demands on clay. So before I can answer: how do you plan on firing it? What temperature (cone) do you plan on firing it to? Are you making functional or non-functional pieces.

Tom

 

Thank you Tom. 

1. Of course functional. (perhaps sometimes decorative, like very small figure sculpture or calligraphy or maybe some ornaments)

2. only firing I can do is using charcoal as fuel, it's not very difficult for me to make a temporary kiln with breaks. I hope I can get to 900°C (1652F) or above, using charcoal and a blower. that should be a cone 4 I think?

btw I just made a psd test , it's  my new clay after sieving.  might be useful:

[Why my clay acts like this?]

32 minutes ago, Babs said:

Btw if you are sieving and washing, you msy be throwing away the fine particles you require for plasticity

Thank you. Yes I  knew that, those were what didn't pass the sieve for a test, therefore I washed them to find out what they are actually and whether they are beneficial or harmful, in order to find out if I have to sieve all the dry powder I've bought or not.

 

[Why my clay acts like this?]

16 hours ago, glazenerd said:

thought was to use it in part with your reddish clay to help even out PSD (particle size distribution).

No, I probably won't mix the reddish one bc I don't have enough, and also for the acidity. So I will try bento... but regarding PSD, 

It has far less impurities than others. photos show the remainder in sieving, after washing (7 times)  and disposing water each time to dump any sutck fine particles,  I  remained with particles that were sink almost immediately and clear water.

After drying, they were still like dried clay (by color and crack pattern), are those just fine sand that are clay like color? 

macro shot:

and should I dispose them or let them to be part of the body?