Alisa and Claus Clausen on mon 27 sep 99
------------------
Dear UK potters,
I have recently been working with 3 clay bodies from the above factory.
All are cone 6 stonewares.
1109 Stoneware with lava flecks
1110 Same body, no flecks
1154 Raku body
With every bisque, almost every piece has at least one crater created in the
surface where you can see there is a chunk of white chalk that forced the =
blow
up. I do not know what the correct term for this is. Here we say =22chalk
springing=22. This clay is purchased in 25 bricks and of course premixed. =
I
wedge also before throwing it of course, but I cannot seem to avoid this
problem. I like the stoneware bodies for throwing - I think they have good
plasticity and are charismatic, especially compared to a white body I was =
using.
Do you have experience with these bodies and do you think that it is =
necessary
for me to blend the body better. I would like a body actually, that I can =
wedge
from the bag, and not have to manually reblend (I mean wet down, and wedge =
up
again, I have no mill) before I use it. That should be a reasonable request
because I have no space to mix my own bodies.
The worse case I had with this clay, was when I handbuilt a large pot. I =
threw
both the top and foot rings and assembled it to the handbuilt portion. The =
pot
dried for over 2 months. During the bisque, both thrown portions completely
exploded, shaving off in large thin slivers. The bisque ware felt almost
powdery and plaster like. Again, I am wondering if the clay, or this =
batch,
could have a fault. I see that there are at least 2 ceramic suppliers in
Stoke-on-Trent. Is that a big ceramic supplier area? I have the =
possibility to
contact the clay supplier, but I am interested in hearing from you (plural) =
if
you have ideas about causes of the problem.
Many thanks,
Alisa in Denmark
Anji Henderson on tue 28 sep 99
Alisa,
Is there any possibility that you are wedging on a
plaster bat, and it is releasing plaster??? Because
plaster does not dry as fast as the clay, and will
cause these types of blow outs??
Hopefully it is that simple, and you can just re do
your plaster wedging area, so you don't have release
of plaster....
Anji
--- Alisa and Claus Clausen wrote:
> ----------------------------Original
> message----------------------------
> ------------------
> Dear UK potters,
> I have recently been working with 3 clay bodies from
> the above factory.
> All are cone 6 stonewares.
> 1109 Stoneware with lava flecks
> 1110 Same body, no flecks
> 1154 Raku body
>
> With every bisque, almost every piece has at least
> one crater created in the
> surface where you can see there is a chunk of white
> chalk that forced the blow
> up. I do not know what the correct term for this
> is. Here we say "chalk
> springing". This clay is purchased in 25 bricks and
> of course premixed. I
> wedge also before throwing it of course, but I
> cannot seem to avoid this
> problem. I like the stoneware bodies for throwing -
> I think they have good
> plasticity and are charismatic, especially compared
> to a white body I was using.
> Do you have experience with these bodies and do you
> think that it is necessary
> for me to blend the body better. I would like a
> body actually, that I can wedge
> from the bag, and not have to manually reblend (I
> mean wet down, and wedge up
> again, I have no mill) before I use it. That should
> be a reasonable request
> because I have no space to mix my own bodies.
>
> The worse case I had with this clay, was when I
> handbuilt a large pot. I threw
> both the top and foot rings and assembled it to the
> handbuilt portion. The pot
> dried for over 2 months. During the bisque, both
> thrown portions completely
> exploded, shaving off in large thin slivers. The
> bisque ware felt almost
> powdery and plaster like. Again, I am wondering
> if the clay, or this batch,
> could have a fault. I see that there are at least 2
> ceramic suppliers in
> Stoke-on-Trent. Is that a big ceramic supplier
> area? I have the possibility to
> contact the clay supplier, but I am interested in
> hearing from you (plural) if
> you have ideas about causes of the problem.
>
> Many thanks,
> Alisa in Denmark
>
=====
Anji
http://www.angelfire.com/md/Anji/
__________________________________________________
Do You Yahoo!?
Bid and sell for free at http://auctions.yahoo.com
Mark & Pauline Donaldson-Drzazga on tue 28 sep 99
----- Original Message -----
From: Alisa and Claus Clausen
To:
Sent: 27 September 1999 19:32
Subject: UK potters - info on clay bodies from Stoke-on-Trent
----------------------------Original message----------------------------
------------------
Dear UK potters,
I have recently been working with 3 clay bodies from the above factory.
All are cone 6 stonewares.
1109 Stoneware with lava flecks
1110 Same body, no flecks
1154 Raku body
With every bisque, almost every piece has at least one crater created in the
surface where you can see there is a chunk of white chalk that forced the
blow
up. I do not know what the correct term for this is. Here we say "chalk
springing". This clay is purchased in 25 bricks and of course premixed. I
wedge also before throwing it of course, but I cannot seem to avoid this
problem. I like the stoneware bodies for throwing - I think they have good
plasticity and are charismatic, especially compared to a white body I was
using.
Do you have experience with these bodies and do you think that it is
necessary
for me to blend the body better. I would like a body actually, that I can
wedge
from the bag, and not have to manually reblend (I mean wet down, and wedge
up
again, I have no mill) before I use it. That should be a reasonable request
because I have no space to mix my own bodies.
The worse case I had with this clay, was when I handbuilt a large pot. I
threw
both the top and foot rings and assembled it to the handbuilt portion. The
pot
dried for over 2 months. During the bisque, both thrown portions completely
exploded, shaving off in large thin slivers. The bisque ware felt almost
powdery and plaster like. Again, I am wondering if the clay, or this
batch,
could have a fault. I see that there are at least 2 ceramic suppliers in
Stoke-on-Trent. Is that a big ceramic supplier area? I have the
possibility to
contact the clay supplier, but I am interested in hearing from you (plural)
if
you have ideas about causes of the problem.
Many thanks,
Alisa in Denmark
Dear Alisa
the clay you are using sounds like Potclays, they have been making very bad
clay and many potters in England have had trouble with their clay. I use
Valentine Clay from Stoke tel No 01782 271200 fax 01782 280008 and ask for
it as soft as they can make it (Number 6). Try them, they are a small family
firm and are very easy to talk to. If you want to phone me then please do so
01769 540471 (fax No as well).
Happy potting Marek
Suzanne Furman on sat 2 oct 99
Alisa.....It sounds like you might have either gotten a bad lot of clay or
are picking up plaster pieces somewhere in your process......I am suspicious
about it being bad clay because it is happening with all three clay bodies
(tho the clay producer could have created this problem). You might also want
to find out if others are having the same problem as you..... Is it happening
to pieces that are thrown directly from a fresh bag of clay?.....or is it
happening to pieces thrown from reprocessed clay?.....I call this
spalling.....and you can see the white speck of substance in the clay body.
There are some ways of handling wedging and reprocessing that will eliminate
your clay getting plaster mixed into it.
1. Wedging........Wedge on a board or table that is canvas
covered.....my tables have plywood tops with canvas stretched over
it......this is an ideal surface to do any wedging or handbuilding.
2. Reprocessing Clay.......Here is a trick that I discovered many years
ago and continue to use this process 30 years later because it works.....I go
to the store and get some plastic square pans....like dish pans.....then get
#1 moulding plaster and pour bats that fill these pans about 2
inches......these bats should be put out to dry in the sun or near a
heater.....when they are dry place them back in the pans......and place a
piece of cloth into the container on top of the bat to keep the slurry away
from the plaster.....I use old sheet squares that are large enough to come
over the top of the container......and then pour in the slurry to fill the
container......it is good if the cloth pieces are large enough to then cover
the top of the slurry.....these containers are small enough to get tucked
into corners and under tables till the clay is stiff enough to hold a
shape......I usually let them stiffen up further standing up on a table till
they are wedgable.....keeping them completely wrapped in cloth helps the clay
dry out evenly so you dont get dry clumps..... and you have kept the clay
safely away from the plaster bat.......and the plastic dish pans that I get
here in the USA make about 25 lbs of reprocessed clay so I put back in the
plastic bags that I saved.........I usually make about twice as many bats as
pans so I can be drying one and using one.....This will eliminate the
possibility of you doing the contaminating and if you still have trouble then
you might try using a different source for clay at least to test and see if
it is perhaps the producers problem.......Well I hope some of this is
helpful......the containers for me make reprocessing easy....and keeps the
clay in handable size pieces......Please let us know what you find out about
your situation......Take Care....Suzanne Kraman
ClayWaves Studio
Marshall, NC
ClayWaves
Studio
--------------------------------------Original
Message---------------------------------------
--- Alisa and Claus Clausen wrote:
> Dear UK potters,
> I have recently been working with 3 clay bodies from
> the above factory.
> All are cone 6 stonewares.
> 1109 Stoneware with lava flecks
> 1110 Same body, no flecks
> 1154 Raku body
>
> With every bisque, almost every piece has at least
> one crater created in the
> surface where you can see there is a chunk of white
> chalk that forced the blow
> up. I do not know what the correct term for this
> is. Here we say "chalk
> springing". This clay is purchased in 25 bricks and
> of course premixed. I
> wedge also before throwing it of course, but I
> cannot seem to avoid this
> problem. I like the stoneware bodies for throwing -
> I think they have good
> plasticity and are charismatic, especially compared
> to a white body I was using.
> Do you have experience with these bodies and do you
> think that it is necessary
> for me to blend the body better. I would like a
> body actually, that I can wedge
> from the bag, and not have to manually reblend (I
> mean wet down, and wedge up
> again, I have no mill) before I use it. That should
> be a reasonable request
> because I have no space to mix my own bodies.
>
> The worse case I had with this clay, was when I
> handbuilt a large pot. I threw
> both the top and foot rings and assembled it to the
> handbuilt portion. The pot
> dried for over 2 months. During the bisque, both
> thrown portions completely
> exploded, shaving off in large thin slivers. The
> bisque ware felt almost
> powdery and plaster like. Again, I am wondering
> if the clay, or this batch,
> could have a fault. I see that there are at least 2
> ceramic suppliers in
> Stoke-on-Trent. Is that a big ceramic supplier
> area? I have the possibility to
> contact the clay supplier, but I am interested in
> hearing from you (plural) if
> you have ideas about causes of the problem.
>
> Many thanks,
> Alisa in Denmark
>
Stephen Mills on sun 3 oct 99
Suzanne,
Here in the UK we have had an ongoing problem in recent years with Lime
Spit from grogs made from reclaimed firebrick, due I suspect to the
decreasing number of furnaces using "heavies" as linings (which need
renewing regularly) and the resulting lack of choice facing the grog
makers, some of whom are unable (or perhaps unwilling) to manufacture
grogs from virgin lime-free material. As always, perceived resistance to
price increases on reliable material seems to drive too many of our
suppliers, who should realize potters are often only too happy to pay
for RELIABLE goods.
I rest my case.
Steve
Bath
UK
In message , Suzanne Furman writes
>----------------------------Original message----------------------------
>Alisa.....It sounds like you might have either gotten a bad lot of clay or
>are picking up plaster pieces somewhere in your process......I am suspicious
>about it being bad clay because it is happening with all three clay bodies
>(tho the clay producer could have created this problem). You might also want
>to find out if others are having the same problem as you..... Is it happening
>to pieces that are thrown directly from a fresh bag of clay?.....or is it
>happening to pieces thrown from reprocessed clay?.....I call this
>spalling.....and you can see the white speck of substance in the clay body.
>There are some ways of handling wedging and reprocessing that will eliminate
>your clay getting plaster mixed into it.
> 1. Wedging........Wedge on a board or table that is canvas
>covered.....my tables have plywood tops with canvas stretched over
>it......this is an ideal surface to do any wedging or handbuilding.
> 2. Reprocessing Clay.......Here is a trick that I discovered many years
>ago and continue to use this process 30 years later because it works.....I go
>to the store and get some plastic square pans....like dish pans.....then get
>#1 moulding plaster and pour bats that fill these pans about 2
>inches......these bats should be put out to dry in the sun or near a
>heater.....when they are dry place them back in the pans......and place a
>piece of cloth into the container on top of the bat to keep the slurry away
>from the plaster.....I use old sheet squares that are large enough to come
>over the top of the container......and then pour in the slurry to fill the
>container......it is good if the cloth pieces are large enough to then cover
>the top of the slurry.....these containers are small enough to get tucked
>into corners and under tables till the clay is stiff enough to hold a
>shape......I usually let them stiffen up further standing up on a table till
>they are wedgable.....keeping them completely wrapped in cloth helps the clay
>dry out evenly so you dont get dry clumps..... and you have kept the clay
>safely away from the plaster bat.......and the plastic dish pans that I get
>here in the USA make about 25 lbs of reprocessed clay so I put back in the
>plastic bags that I saved.........I usually make about twice as many bats as
>pans so I can be drying one and using one.....This will eliminate the
>possibility of you doing the contaminating and if you still have trouble then
>you might try using a different source for clay at least to test and see if
>it is perhaps the producers problem.......Well I hope some of this is
>helpful......the containers for me make reprocessing easy....and keeps the
>clay in handable size pieces......Please let us know what you find out about
>your situation......Take Care....Suzanne Kraman
>ClayWaves Studio
>Marshall, NC
> ClayWaves
>Studio
>--------------------------------------Original
>Message---------------------------------------
>--- Alisa and Claus Clausen wrote:
>
>> Dear UK potters,
>> I have recently been working with 3 clay bodies from
>> the above factory.
>> All are cone 6 stonewares.
>> 1109 Stoneware with lava flecks
>> 1110 Same body, no flecks
>> 1154 Raku body
>>
>> With every bisque, almost every piece has at least
>> one crater created in the
>> surface where you can see there is a chunk of white
>> chalk that forced the blow
>> up. I do not know what the correct term for this
>> is. Here we say "chalk
>> springing". This clay is purchased in 25 bricks and
>> of course premixed. I
>> wedge also before throwing it of course, but I
>> cannot seem to avoid this
>> problem. I like the stoneware bodies for throwing -
>> I think they have good
>> plasticity and are charismatic, especially compared
>> to a white body I was using.
>> Do you have experience with these bodies and do you
>> think that it is necessary
>> for me to blend the body better. I would like a
>> body actually, that I can wedge
>> from the bag, and not have to manually reblend (I
>> mean wet down, and wedge up
>> again, I have no mill) before I use it. That should
>> be a reasonable request
>> because I have no space to mix my own bodies.
>>
>> The worse case I had with this clay, was when I
>> handbuilt a large pot. I threw
>> both the top and foot rings and assembled it to the
>> handbuilt portion. The pot
>> dried for over 2 months. During the bisque, both
>> thrown portions completely
>> exploded, shaving off in large thin slivers. The
>> bisque ware felt almost
>> powdery and plaster like. Again, I am wondering
>> if the clay, or this batch,
>> could have a fault. I see that there are at least 2
>> ceramic suppliers in
>> Stoke-on-Trent. Is that a big ceramic supplier
>> area? I have the possibility to
>> contact the clay supplier, but I am interested in
>> hearing from you (plural) if
>> you have ideas about causes of the problem.
>>
>> Many thanks,
>> Alisa in Denmark
>>
>
--
Steve Mills
Bath
UK
home e-mail: stevemills@mudslinger.demon.co.uk
work e-mail: stevemills@bathpotters.demon.co.uk
own website: http://www.mudslinger.demon.co.uk
BPS website: http://www.bathpotters.demon.co.uk
| |
|
