Ivor and Olive Lewis on fri 4 nov 05
Dear Jason Palmer,
Thank you for making a contribution to this thread. You certainly give =
us all a lot of things to think about as well as some good suggestions =
relating to modifying throwing techniques.
Perhaps you could explain what a "Water Tabeling" is. Around these parts =
a "Water Table" is the level at which the soil becomes saturated and =
free water flows from spring lines, a rather infrequent happening. I =
think recent readings from nearby bores showed that it was at a depth of =
40 feet below the surface. Above the Water Table there is a small amount =
of capillary water and above that the land is dry, bone dry. So I am =
having a problem relating "Water Tabeling" to a few pounds of plastic =
clay and a pot about eighteen inches high. If "Water Tabeling" exists =
one possible prediction would be that water would flow towards the lower =
part of a pot leaving the clay above drier and also stiffer
You also suggest that the solid materials are suspended in water=20
..." as i said clay particles are suspended in water...not the other way =
around. this means that as you go higher/ thinner with your walls...the =
percent of clay particles to the percent of water particles actually =
decreases....."...
I have no doubt that your conclusions are based on your observations. =
But I fail to see where Physics is being used.
Best regards,
Ivor Lewis.
Redhill,
South Australia.
skiasonaranthropos@FSMAIL.NET on fri 4 nov 05
Hello Jason,
Despite reading your message a few times Im still puzzled about what you
describe as the physics of clay and therefore I would be grateful if you
would elaborate, with particular reference to:
1. =93...clay particles are hexogonal shaped with water molecules suspending=
the whole solution=94 Are you suggesting a clay and water mixture is a
solution?
2. Further information on the role of deflocculants in destroying the
polarity of water as this differs to the more common explanation of them
altering the respective attraction forces of particles by modifying edge
charges
3. =93... the clay to push away from itself and become more fluid than it
really is=94 What do you mean by =93than it really is=94 Surely there is no =
true
fluidity of a slip, rather it will vary depending on the combined effect
of a range of factors including the properties of the solids, amount of
water and state of deflocculation
4. =93Water tabeling out=94 This is a new term to me so an explanation of th=
e
phenomenon would be much appreciated
5. =93this means that as you go higher/ thinner with your walls...the
percent of clay particles to the percent of water particles actually
decreases=94 Could you explain? Have you measured this?
6. =93... the clay WILL NOT go any taller. as you pull up...the clay
particles spread out...and then slither their way back down due to
gravity.=94 Isnt the height limit simply related to the materials ability to=
support its own mass?
Many thanks, and I hope you will submit further explanation
Regards,
Antony
Ivor and Olive Lewis on sat 5 nov 05
Right Jason,
I have read your long essay and pick on just one portion for comment.
You say,<something like a refrigerator. Add enough magnets to the fridge and you =
have a pretty good attachment.now if you pulled on every one of those =
magnets.you would move the fridge, right. .>>
I am willing to think of the crystals of clay as being the Magnets. And =
the water molecules as being the magnets. In fact I have made model =
using magnets ( a fact I have reported to Clayart Members some time =
ago).To simulate the water molecules I used pure Iron Powder. It is an =
unsafe analogy since pure Iron Powder has no magnetic flux except that =
induced by the magnets. The strange thing is a mixture of the two =
becomes a plastic solid. Quite amazing.
However in real life we are dealing with the power of electrons and =
protons. Using our magnetic analogy to interpret the relationship =
between clay and water leads to an amazing conclusion that is =
unbelievable. It is a concept an ordinary mind cannot accept because it =
is incomprehensible and contrary to all of our experiences. Anyone who =
dared to utter it would be deemed insane.
If you search the archives I am sure you will find mention of this in =
posts I have sent to Clayart in the past.
Best regards.
Ivor
----- Original Message ----- =20
From: boobyagga@juno.com=20
To: iandol@westnet.com.au=20
Sent: Saturday, 5 November 2005 4:11
Subject: Re: response for throwing tall. the physics of it all.=20
hey ivor. thanks for the reply. sorry about the confusion. i just sent =
the reply to the moderator of clayart for posting. i figgured that other =
people probably share your question and will benifit from the response. =
i reposted your email you sent me so they could know where i was coming =
from in answering questions they havent read. hope you dont mind. :-)
anyways...heres the post in its entirety (beware...its long) so you =
dont have to hunt it down on clayart. thanks and best of luck.
p.s....when you get the daily email from clay art..is it just a big =
jumble of words with no paragraphing?? mine is and it makes it =
impossible to read at all. just wondering if that is a problem with clay =
art or something regarding how im opening it. thanks.=20
A further explanation to the post I made earlier. I got this as a =
question and thought that a further explanation may benefit everyone =
else with the same questions.=20
=20
---"Dear Jason Palmer,
Thank you for making a contribution to this thread. You certainly give =
us all a lot of things to think about as well as some good suggestions =
relating to modifying throwing techniques.
Perhaps you could explain what a "Water Tabeling" is. Around these =
parts a "Water Table" is the level at which the soil becomes saturated =
and free water flows from spring lines, a rather infrequent happening. I =
think recent readings from nearby bores showed that it was at a depth of =
40 feet below the surface. Above the Water Table there is a small amount =
of capillary water and above that the land is dry, bone dry. So I am =
having a problem relating "Water Tabeling" to a few pounds of plastic =
clay and a pot about eighteen inches high. If "Water Tabeling" exists =
one possible prediction would be that water would flow towards the lower =
part of a pot leaving the clay above drier and also stiffer
You also suggest that the solid materials are suspended in water=20
..." as i said clay particles are suspended in water...not the other =
way around. this means that as you go higher/ thinner with your =
walls...the percent of clay particles to the percent of water particles =
actually decreases....."...
I have no doubt that your conclusions are based on your observations. =
But I fail to see where Physics is being used.
Best regards,
Ivor Lewis.
Redhill,
South Australia."
-------------
=20
Hmmm.lets see.how best to explain this. True.that is the correct =
definition of water tabeling. Water tabeling out is simply the name that =
I have heard it referred to around here. And water tabeling is not my =
own original theory.it's something ive picked up from other people =
around me and given some thought and consideration to.being a science =
nut.it's kind of interested me. This water tabeling has almost no =
relation to the water table of ground water I believe. Someone else may =
be able to relate them.not me.=20
Now when you said that the water flows downward to the bottom of the =
pot.that is true. I guess physics isn't exactly the right word to =
associate with this.its more of a chemistry thing. Water tabeling does =
happen because the water flows towards gravities pull.. but while it =
does this it drags the clay with it.=20
Water is an absolutely amazing molecule. So simple and so strong.. I =
guess that's why nothing can survive without it. Water is =
bipolar.meaning it bonds quickly and strongly with almost anything. =
That's why it is the universal solvent. The water actually bonds to the =
clay.not in a chemical bond way.but in an electron attachment way. Think =
of water as a very very strong, tiny magnet and clay as something like a =
refrigerator. Add enough magnets to the fridge and you have a pretty =
good attachment.now if you pulled on every one of those magnets.you =
would move the fridge, right. Water will always find a level spot. =
Always. It finds the lowest area it can.that's why construction crews =
use it to level concrete slabs. So a pot is just suspended water. =
Naturally it wants to fall down to the wheel head.and because of the =
bond between the hundreds of water molecules and the relatively large =
clay particle the clay particle is drug down with it.the clay resists =
the movement though.slowing the process.=20
Maybe that helps a little with that.=20
As to the clay particles % decreasing.that is in the bottom of the =
pot. The clay particles are easy to raise up. Because of their size and =
shape they want to follow your hand.path of least resistance.. the water =
works its way to the bottom.=20
Water tabeling usually happens about 3 to 5 inches from the wheel =
head. Right where your walls usually thin out from the base curve and =
become actual walls. There they support the most weight per particle out =
of any other section of the pot. So as you raise up a wall.you are =
bringing a number of clay particles up.as you do this.the mechanical =
energy of your hand pulling is enough to overcome the attraction of clay =
to water.pulling them apart.so clay goes up.and some water stays. Now =
we are talking minute amounts.a hundred or thousand parts per million. =
But when combined with the thinning wall and the added weight on the =
wall it amounts to something significant. Take a plastic bag of clay and =
just set it out for a few days.in a day or so the bottom will eventually =
start oozing (for lack of a better word) out.the whole block starts to =
settle. The only way to stop this from happening is to get rid of the =
water.as you get rid of the water the hexagonal shapes of the clay =
particles intermesh.creating a puzzle of particles.
The other way to prevent water tabeling is to throw thicker. Thicker =
walls reduce the weight distribution, which decreases the likelihood of =
water tabeling exponentially. Making a wall 1/8 or =BC inch thicker can =
allow you to make a pot 4 or more inches taller depending on the clay. =
Now if you want a full explanation of all the factors of thicker =
walls.the added mass increases the total attachment between the =
particles of the wall (a big, long explanation could come with this =
part.but the over all outcome is very very minute.its not a major =
factor) it also inhibits the random movement of particles in the wall. =
All particles are moving randomly. Everything from your kitchen counter =
tops to the air we breathe. And the same is true with water and =
clay.they move in the walls..but as you add more clay around them they =
have less area to move in. its like if you were in a crowded room as =
opposed to a room with only a few people..You would have much more space =
to move around in. same with clay.it can move much easier and settles =
out much faster with thinner walls. It will settle until all the water =
is gone.=20
=20
Now if you want to throw a very tall, thin, elegant pot my suggestions =
are this. It is not a crime or sin to trim. I've learned that trimming =
in itself is an art form. Use more clay than you could possibly need for =
the thing you are wanting to make. Throw it taller than you want it..and =
very thick.for me very thick is =BC to =BD inches. This gives you great =
control over the clay as you throw (thin clay doesn't like to obey your =
hands much) and prevents massive amounts of settling and warping. Let it =
dry out a bit. I leave mine spinning slowly on the wheel with a fan =
blowing on it for about 2 hours or so. Come back and trim it until you =
reach the softer inner sections of the wall. Continue drying and trim =
more. This can be repeated until the desired wall width has been reached =
(tap on the wall and listen to the sound to judge thickness). Using this =
I have made some absolutely gorgeous porcelain vases that are easily =
transparent. This is how the Greeks made their famous pots that were =
enormous and only 1/16 of an inch or so thick. Like egg shells. They =
were amazing at this. =20
Hmmm.this is a very long entry.longer than I though it would be. Sorry =
about that. I really hope ive answered your question. It seems like ive =
just rambled on aimlessly. I will see if I can find a website with a =
better description and maybe some pictures from microscopes and such of =
the process. I've seen some before and they really do help you =
understand.=20
Really water tabeling is a small detail in the process.one of those =
things that as you are throwing just suddenly happens and all you can =
say is "dangit!" and cut it off and rewedge it. It mostly just happens =
as you get too thin with too much stress and time. If you want to really =
see water tabeling.get some good and wet clay.and try and throw a tall =
cylinder.nothing fancy.just straight up. It will reach a maximum height =
and never seem to get taller. You can pull and pull and pull and it will =
go nowhere. That is water tabeling. The biggest factor in throwing tall =
is diffusion of water.solve that with the slip solution. That will help =
you the most. I wouldn't worry about water tabeling too much.=20
I noticed you said you were in Australia.and its not Sydney :-D.I =
didn't know there were other cities in Australia with real populations. =
No just kidding. How do you like it down there? I've always wanted to =
visit there.even though it is literally halfway around the world from =
me. Fun stuff.=20
Well sorry for this being soooo long. Thanks for the reply. They make =
my day.=20
=20
Jason Palmer
Beaumont, Texas USA
Farfl's House on sun 6 nov 05
Ah, finally! A kindred spirit!
Once I braved 30 degrees below weather to sort through 78rpm recordings
in a barn in Upstate New York.
Um...how to relate this to clay...er.....ah, yes! The chill invaded my
fingers to the very bone, making it nigh impossible to throw the next day!
-Steven Lederman
Steve Slatin wrote:
>Steve Slatin --
>
>Drove downtown in the rain
>9:30 on a Tuesday night
>Just to check out the
>Late night record shop
>
>
>
>
>
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Steve Slatin on sun 6 nov 05
Dear Ivor --
Now you know how much I enjoy your posts, but this one
is just a tease. I'll bet if I look in the archived
I'll find you have many hundreds of posts ... am I to
read them all and try to guess which is the one the
very reading of which is license to madness? Come
clean with us! At least provide the citation or the
date, it's only sporting ...
Best wishes -- Steve Slatin
--- Ivor and Olive Lewis
wrote:
> Using our magnetic analogy
> to interpret the relationship between clay and water
> leads to an amazing conclusion that is unbelievable.
> It is a concept an ordinary mind cannot accept
> because it is incomprehensible and contrary to all
> of our experiences. Anyone who dared to utter it
> would be deemed insane.
>
> If you search the archives I am sure you will find
> mention of this in posts I have sent to Clayart in
> the past.
Steve Slatin --
Drove downtown in the rain
9:30 on a Tuesday night
Just to check out the
Late night record shop
__________________________________
Yahoo! Mail - PC Magazine Editors' Choice 2005
http://mail.yahoo.com
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