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new peter pugger! epsom salts for "short" clay?

updated fri 3 nov 06

 

Cheryl Weickert6 on sat 21 oct 06


Oh, the clay comes out warm too... I so have Peter Pugger envy! sigh,
maybe someday.

Pinky in cold MN

On Sat, 21 Oct 2006 17:14:34 -0700, Scott Harrison
wrote:

What is interesting is when I
>extrude during the class time the students are rapt with attention.
>The boys seem to regard the extrusion as a more of a defication
>analogy while the girls seem to be in the phallus camp, even coming
>over to help with the pug and somewhat surprised at how warm it is.
>All I can do to keep a straight face...
>
>Scott Harrison
>South Fork High School
>Humboldt Redwoods CA

Scott Harrison on sat 21 oct 06


Had a brief tour of the factory and picked up a new VPM-20 from Jared
at Peter Pugger last weekend. I'm working on the learning curve for
this model. I have read through the extensive Clayart archives on
this and there is some mention of adding Epsom salts to compensate
for "short" clay. What amount should I add to a full load to help
this? Some pug loads will extrude with a 5 foot 3" section all at
once and some come out in 15" sections and break off. As a side note,
I am busy getting caught up with all the scraps around the classroom
and am enjoying the pugger quite a bit. What is interesting is when I
extrude during the class time the students are rapt with attention.
The boys seem to regard the extrusion as a more of a defication
analogy while the girls seem to be in the phallus camp, even coming
over to help with the pug and somewhat surprised at how warm it is.
All I can do to keep a straight face...

Scott Harrison
South Fork High School
Humboldt Redwoods CA

Lisa Skeen on sun 22 oct 06


If you've mixed a full batch, yes, it comes out warm from the friction of
the mixing process. There is a downside to that tho, and that is that the
warmth evaporates some of the water in the clay and that can be a problem.

For "short" clay, I open the hopper, poke holes in the mass with a hammer
handle, fill those holes with clay slop and mix some more. :) Works a
treat. If you just pour the wet clay in on top of the mass, you'll get a
bad case of the "spinnies", which means the whole mass of clay will just
spin around in the chamber and not get mixed, and then you have to chase
that down with dry clay and it's a vicious circle. :( I just discovered the
hammer handle trick and like it a lot.

L
----- Original Message -----
From: "Cheryl Weickert6"
> Oh, the clay comes out warm too... I so have Peter Pugger envy! sigh,
> maybe someday.

Ron Roy on sun 22 oct 06


Hi Scott,

2 lb dry Epsom per 1000 lb dry clay material - make sure the Epsom is
completely disolved and add it in with the water.

You may find you only need 1 lb for stoneware clay.

RR



>Had a brief tour of the factory and picked up a new VPM-20 from Jared
>at Peter Pugger last weekend. I'm working on the learning curve for
>this model. I have read through the extensive Clayart archives on
>this and there is some mention of adding Epsom salts to compensate
>for "short" clay. What amount should I add to a full load to help
>this? Some pug loads will extrude with a 5 foot 3" section all at
>once and some come out in 15" sections and break off. As a side note,
>I am busy getting caught up with all the scraps around the classroom
>and am enjoying the pugger quite a bit. What is interesting is when I
>extrude during the class time the students are rapt with attention.
>The boys seem to regard the extrusion as a more of a defication
>analogy while the girls seem to be in the phallus camp, even coming
>over to help with the pug and somewhat surprised at how warm it is.
>All I can do to keep a straight face...
>
>Scott Harrison

Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0

Gail Dapogny on sun 22 oct 06


I suspect and hope that Ron Roy will chime in here -- he advised me
on this subject. Since we also have a Peter Pugger, I think my
advice might be relevant to you. When making porcelain in the PP, we
mix 45 grams of epsom salts with a couple of cups of water (heat it
up in the microwave for faster dissolving), and add that to the total
full load. Works great.
Gail

Gail Dapogny
Ann Arbor, Michigan
gdapogny@umich.edu
www.pottersguild.net
www.claygallery.org


On Oct 21, 2006, at 8:14 PM, Scott Harrison wrote:

> Had a brief tour of the factory and picked up a new VPM-20 from Jared
> at Peter Pugger last weekend. I'm working on the learning curve for
> this model. I have read through the extensive Clayart archives on
> this and there is some mention of adding Epsom salts to compensate
> for "short" clay. What amount should I add to a full load to help
> this? Some pug loads will extrude with a 5 foot 3" section all at
> once and some come out in 15" sections and break off. As a side note,
> I am busy getting caught up with all the scraps around the classroom
> and am enjoying the pugger quite a bit. What is interesting is when I
> extrude during the class time the students are rapt with attention.
> The boys seem to regard the extrusion as a more of a defication
> analogy while the girls seem to be in the phallus camp, even coming
> over to help with the pug and somewhat surprised at how warm it is.
> All I can do to keep a straight face...
>
> Scott Harrison
> South Fork High School
> Humboldt Redwoods CA
>
> ______________________________________________________________________
> ________
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at
> melpots@pclink.com.
>
>

Fredrick Paget on mon 23 oct 06


>
>As to potters being sensitive to Epsom salts - Tuckers uses it in many of
>their clay bodies and there have been no complaints. Aren't they used for
>foot baths?
>
>RR

Remember the proverbial "Dose of salts"? They refer to Epsom salts.
It used to be used as a purgative.
Fred Paget
--
Twin Dragon Studio
Mill Valley, CA, USA

Ivor and Olive Lewis on mon 23 oct 06


Dear Scott Harrison and Friends,
I have been reading some of the replies to the original post. For some =
reason alarm bells started to ring with regard to the necessity to add =
Magnesium Sulphate. I am not saying that adding Epsom Salts will not =
perform the duty as described. What concerns me is the premise =
describing the problem, that of "Short Clay".
Now I do not mind being told I am wrong on this one, but why would the =
clay be short? Before treating the symptoms an answer is needed to this =
question.=20
Reading your post gives no clue as to the mineral composition of the =
clays that your students are reclaiming. Nor do we know the full history =
of what is being reclaimed.
My experience when dealing with large numbers of students is that clay, =
as it is used, gets "Washed Out". Vast volumes of water used by students =
leads to discarding the supernatant water from above thicker slurry and =
firmer slops. What is thrown away contains significant quantities of =
superfine clay particles, the fraction which contributes most to =
plasticity ( and the best stuff for Terra Sig ! ) Adding Epsom Salts =
will not replace that lost or compensate for its beneficial qualities. =
My solution was to add about five percent by weight of Ball Clay, =
scattered over clay that had been bailed out onto the plaster slabs. =
This restored plasticity without needing to add a strongly acidic =
substance to the clay that might at some time cause problems for a =
student with a sensitive skin.
That scatological and erotic phase will die away with time. Seems to be =
a universal trait.
Best regards,
Ivor Lewis.
Redhill,
South Australia.

Scott Harrison on mon 23 oct 06


Ivor,
I think you're right on the money with the clay getting "washed
out". Wheel students are using their clay several times and dumping
it into reclaim while the slip water is discarded. I will try the
ball clay to see how that works. We are using two clays at this time,
Calico Red and Cone 5 Bmix w/sand and they usually get combined in
reclaim.

Scott Harrison
South Fork High School
Humboldt Redwoods CA


On Oct 23, 2006, at 12:21 AM, Ivor and Olive Lewis wrote:

> Dear Scott Harrison and Friends,
> I have been reading some of the replies to the original post. For
> some reason alarm bells started to ring with regard to the
> necessity to add Magnesium Sulphate. I am not saying that adding
> Epsom Salts will not perform the duty as described. What concerns
> me is the premise describing the problem, that of "Short Clay".
> Now I do not mind being told I am wrong on this one, but why would
> the clay be short? Before treating the symptoms an answer is needed
> to this question.
> Reading your post gives no clue as to the mineral composition of
> the clays that your students are reclaiming. Nor do we know the
> full history of what is being reclaimed.
> My experience when dealing with large numbers of students is that
> clay, as it is used, gets "Washed Out". Vast volumes of water used
> by students leads to discarding the supernatant water from above
> thicker slurry and firmer slops. What is thrown away contains
> significant quantities of superfine clay particles, the fraction
> which contributes most to plasticity ( and the best stuff for Terra
> Sig ! ) Adding Epsom Salts will not replace that lost or compensate
> for its beneficial qualities. My solution was to add about five
> percent by weight of Ball Clay, scattered over clay that had been
> bailed out onto the plaster slabs. This restored plasticity without
> needing to add a strongly acidic substance to the clay that might
> at some time cause problems for a student with a sensitive skin.
> That scatological and erotic phase will die away with time. Seems
> to be a universal trait.
> Best regards,
> Ivor Lewis.
> Redhill,
> South Australia.
>
> ______________________________________________________________________
> ________
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at
> melpots@pclink.com.

Ron Roy on mon 23 oct 06


Hi Scott,

Just remember - you are changing the clay body - for instance, you may find
it leaking after such a random addition.

Best to do some absorption testing on the original bodies and compare them
with the altered clay if you are concerned with function.

As to potters being sensitive to Epsom salts - Tuckers uses it in many of
their clay bodies and there have been no complaints. Aren't they used for
foot baths?

RR


>Ivor,
> I think you're right on the money with the clay getting "washed
>out". Wheel students are using their clay several times and dumping
>it into reclaim while the slip water is discarded. I will try the
>ball clay to see how that works. We are using two clays at this time,
>Calico Red and Cone 5 Bmix w/sand and they usually get combined in
>reclaim.
>
>Scott Harrison

Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0

Ron Roy on mon 23 oct 06


Hi Gail,

How much dry clay?

RR

>I suspect and hope that Ron Roy will chime in here -- he advised me
>on this subject. Since we also have a Peter Pugger, I think my
>advice might be relevant to you. When making porcelain in the PP, we
>mix 45 grams of epsom salts with a couple of cups of water (heat it
>up in the microwave for faster dissolving), and add that to the total
>full load. Works great.
>Gail
>
>Gail Dapogny

Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0

Ivor and Olive Lewis on tue 24 oct 06


Dear Scott Harrison,

If you check the literature i.e. Frank Hamer, Daniel Rhodes or Robert =
Fournier for Epsom Salts or Magnesium Sulphate you will find that it is =
recommended for thickening or suspending glazes that settle rapidly. =
Little is said about its use to promote plastic properties.

I think you will be successful,

Best regard,=20

Ivor

Ron Roy on sun 29 oct 06


It works very well for flocculating clay - been using it now for 20 years -
it's the perfect answer for deflocced clay.

If the clay is short because students are washing away fine particles
during centering and throwing - then save the throwing sludge and add it
back in.

If the clay is naturally not very plastic and only becomes so when aged -
then adding disolved Epsom salts will do the trick.

RR


>If you check the literature i.e. Frank Hamer, Daniel Rhodes or Robert
>Fournier for Epsom Salts or Magnesium Sulphate you will find that it is
>recommended for thickening or suspending glazes that settle rapidly.
>Little is said about its use to promote plastic properties.
>
>I think you will be successful,
>
>Best regard,
>
>Ivor

Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0

Gail Dapogny on mon 30 oct 06


Ron advised me to have our guild add it to porcelain that we make in
our Peter Pugger. It did indeed help. We add 49 dissolved grams to a
408 pugger load.

Gail Dapogny in Ann Arbor

On Oct 29, 2006, at 1:47 PM, Ron Roy wrote:

> It works very well for flocculating clay - been using it now for 20
> years -
> it's the perfect answer for deflocced clay.
>
> If the clay is short because students are washing away fine particles
> during centering and throwing - then save the throwing sludge and
> add it
> back in.
>
> If the clay is naturally not very plastic and only becomes so when
> aged -
> then adding disolved Epsom salts will do the trick.
>
> RR
>
>
>> If you check the literature i.e. Frank Hamer, Daniel Rhodes or Robert
>> Fournier for Epsom Salts or Magnesium Sulphate you will find that
>> it is
>> recommended for thickening or suspending glazes that settle rapidly.
>> Little is said about its use to promote plastic properties.
>>
>> I think you will be successful,
>>
>> Best regard,
>>
>> Ivor
>
> Ron Roy
> RR#4
> 15084 Little Lake Road
> Brighton, Ontario
> Canada
> K0K 1H0
>
> ______________________________________________________________________
> ________
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at
> melpots@pclink.com.
>
>

Ivor and Olive Lewis on tue 31 oct 06


Dear Ron Roy,=20

Thank you for your message of Oct 29.

<years - it's the perfect answer for deflocced clay.

If the clay is short because students are washing away fine particles =
during centering and throwing - then save the throwing sludge and add it =
back in.

If the clay is naturally not very plastic and only becomes so when aged =
- then adding disolved Epsom salts will do the trick.>>

Your first statement I can follow since Epsom Salts is a substance that =
acidifies aqueous suspensions when it dissolves and will neutralise =
alkali deflocculating additives.

I thoroughly agree with your suggestion to reclaim all of the discards =
from throwing.

But your final statement has me perplexed. Are you telling us that an =
addition of Magnesium Sulphate will reduce particle size of clay and =
cause it to divide into smaller and finer sheet crystals as is supposed =
to happen when clay is wet aged for a long period of time to improve =
workability. Or does this chemical do other things to the clay?

Best regards,

Ivor Lewis.
Redhill,
South Australia.

Ron Roy on thu 2 nov 06


Hi Ivor,

You can think of Epsom salts as something that will instantly age clay -
flocculate it - increase what we call platicity

When clay is recycled it is as if the aging process has to start again - I
am suggesting adding Epsom salts to see if that will restore plasticy. If
it does not work then don't do it again.

Plasticity is not only related to particle size - particle charge is a very
important aspect of clay plasticity - and is sometimes more important..

RR


>If the clay is naturally not very plastic and only becomes so when aged -
>then adding disolved Epsom salts will do the trick.>>
>
>Your first statement I can follow since Epsom Salts is a substance that
>acidifies aqueous suspensions when it dissolves and will neutralise alkali
>deflocculating additives.
>
>I thoroughly agree with your suggestion to reclaim all of the discards
>from throwing.
>
>But your final statement has me perplexed. Are you telling us that an
>addition of Magnesium Sulphate will reduce particle size of clay and cause
>it to divide into smaller and finer sheet crystals as is supposed to
>happen when clay is wet aged for a long period of time to improve
>workability. Or does this chemical do other things to the clay?
>
>Best regards,
>
>Ivor Lewis.

Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0