Ben Morrison on sun 13 may 12
With most of my pots and most of my glazes little happens below 450. It is =
a stress on weaker pots especially if they are thrown in sections, or slabb=
ed pots. Any pots that have thick spots next to thin spots seem to have mor=
e difficulty in heat/cooling stress situations. What I was taught in colleg=
e and it may be completely wrong, is that once paper stops catching on fire=
the plugs can be taken out of the door and the damper pulled to begin cool=
ing quicker. After an hour or so the door can be cracked very slightly 1" o=
r less, after another hour it can be cracked a bit more, and then as soon a=
s it's not burning your face to unload, it can be opened and unloaded.
I do this frequently with my pots in my kiln. I often unload with gloves wh=
en they are too hot to hold probably 350 degrees I'd guess. Some of my alte=
red pots don't like this activity, so I don't push them, I allow them to co=
ol much more.
It might be somewhat stressful on the pots to do this, but when you think a=
bout it, much of our ware is required to do much more than this by our cust=
omers. Often very hot food at 350 degrees is put on my own plates right out=
of the oven unevenly heating spots of my ware and not heating other spots.
________________________________
From: William & Susan Schran User
To: Clayart@LSV.CERAMICS.ORG
Sent: Sunday, May 13, 2012 7:43 PM
Subject: Re: Removing pots from a hot kiln
On 5/13/12 7:20 PM, "gina mars" wrote:
>I'm looking for any info you may have on what is the appropriate temp to
>open a gas kiln filled with copper reds. If it's 150 degrees or so I open
>it and take
>them out slowly as I can without sweating to much. Someone I met says
>that copper reds are still forming
>to about 100 degrees. I'm not really buying that. Any thoughts?
Wouldn't think much is happening with the glaze at 150F, or even at 3
times hotter.
As long as you can hold the pots with your bare hand, you're ok to unload.
Might have some crazing exposing hot glazes to cold outdoor temps.
Bill
--
William "Bill" Schran
wschran@cox.net
wschran@nvcc.edu
http://www.creativecreekartisans.com
gina mars on sun 13 may 12
Hi All, I'm looking for any info you may have on what is the appropriate =
=3D
temp to
open a gas kiln filled with copper reds. If it's 150 degrees or so I =3D
open it and take
them out slowly as I can without sweating to much. Someone I met says =3D
that copper reds are still forming
to about 100 degrees. I'm not really buying that. Any thoughts?=3D20
Thank you, Gina Mars
www.marspottery.net
William & Susan Schran User on sun 13 may 12
On 5/13/12 7:20 PM, "gina mars" wrote:
>I'm looking for any info you may have on what is the appropriate temp to
>open a gas kiln filled with copper reds. If it's 150 degrees or so I open
>it and take
>them out slowly as I can without sweating to much. Someone I met says
>that copper reds are still forming
>to about 100 degrees. I'm not really buying that. Any thoughts?
Wouldn't think much is happening with the glaze at 150F, or even at 3
times hotter.
As long as you can hold the pots with your bare hand, you're ok to unload.
Might have some crazing exposing hot glazes to cold outdoor temps.
Bill
--
William "Bill" Schran
wschran@cox.net
wschran@nvcc.edu
http://www.creativecreekartisans.com
Snail Scott on mon 14 may 12
On 5/13/12 7:20 PM, "gina mars" wrote:
> Someone I met says
> that copper reds are still forming
> to about 100 degrees. I'm not really buying that. Any thoughts?
Seems unlikely. However...
Cadmium reds can visibly change colors in that
few-hundred-degree temp range, looking black
while still hot and turning red as they cool. A low-
fire load, if the kiln is opened while it's still a bit
hot, can look really weird that way. Perhaps it's
cadmium reds, not copper reds, that the person
had in mind?
-Snail
Lis Allison on mon 14 may 12
What about opening a hot electric kiln? Does opening it at 300F damage the
thermocouples or anything else?
Lis
--
Elisabeth Allison
Pine Ridge Studio
website: www.pine-ridge.ca
Pottery blog: www.studio-on-the-ridge.blogspot.com
Garden blog: www.garden-on-the-ridge.blogspot.com
Lee on mon 14 may 12
I was happy to spend some time with my Mashiko friend Douglas Black at
the Mungyeong Chasabal Festival.
Doug does Hikidashi-guro, pulling his pots out of the kiln at high
stoneware temps.
The critical time when you don't want fast cooling is at quartz
inversion. Just avoid those temps and typically, you are okay. The
major stress on Raku pots are when they are water quenched. If you
want structural integrety, air cool instead of water quenching.
You can see some of Doug's work at his facebook page below:
http://tinyurl.com/cm3of64
--
=3DA0Lee Love in Minneapolis
http://mingeisota.blogspot.com/
=3DA0"Ta tIr na n-=3DF3g ar chul an tI=3D97tIr dlainn trina ch=3DE9ile"=3D9=
7that is, =3D
"The
land of eternal youth is behind the house, a beautiful land fluent
within itself." -- John O'Donohue
Snail Scott on mon 14 may 12
On May 14, 2012, at 7:31 AM, Lis Allison wrote:
> What about opening a hot electric kiln? Does opening it at 300F damage th=
e
> thermocouples or anything else?
Thermocouples are probably the least affected
of all the components. First, crash-cooling through
the lower temps (when the glaze is hardened and
brittle) can cause crazing and even cracking of the
fired ceramic work due to thermal shock. Second,
the kiln brick itself is rather brittle, and crash-cooling
by opening too soon is rough on the brick. The lid in
particular is vulnerable to thermal-shock cracking.
It's not likely to result in catastrophic failure, but I'd
have to be pretty desperate to unload before I'd want
to further compromise the long-term condition of
expensive equipment. (Have I ever been that
desperate? Yep, I have. Not often, but sometimes
shit happens.) It's your kiln, though, and you're a
grown-up; make your own choices.
-Snail
Ben Morrison on mon 14 may 12
When salt firing you should remove the thermocouple from the hot kiln befor=
e introducing salt. The thermocouple jacket (if one is used) is vulnerable =
to temperature shock. I can't imagine that the thermocouple would sustain d=
amage in a rapid cool from 350 if they can withstand going in and out of a =
gas kiln at top temperature.
-Ben
________________________________
From: Lis Allison
To: Clayart@LSV.CERAMICS.ORG
Sent: Monday, May 14, 2012 5:31 AM
Subject: Re: Removing pots from a hot kiln
What about opening a hot electric kiln? Does opening it at 300F damage the
thermocouples or anything else?
Lis
--
Elisabeth Allison
Pine Ridge Studio
website: www.pine-ridge.ca
Pottery blog: www.studio-on-the-ridge.blogspot.com
Garden blog: www.garden-on-the-ridge.blogspot.com
Maggie Furtak on tue 15 may 12
=3D0A=3D0A=3DA0I find the easiest solution to this is to schedule the kiln =
so tha=3D
t it is cooling overnight, and totally cool by the time my furry friend dec=
=3D
ides it's time for breakfast around 5:30 a.m. =3DA0That way I'm not tempted=
t=3D
o open it too soon, because I am snoozing away. =3DA0(By furry friend, I me=
an=3D
the hound dog, not my husband. =3DA0Mike is relatively furless and since h=
e =3D
has opposable thumbs, can open the the cabinet with the people chow in it b=
=3D
y himself in the morning). =3DA0(: =3DA0=3D0A=3D0AKnow thyself! =3DA0If you=
are impat=3D
ient, set up impatient-ness checks and balances so you don't ruin your good=
=3D
work. =3DA0If you have blank canvas syndrome and can't get started, set up=
l=3D
aziness prods, like putting the coffee maker in the studio. =3DA0If you are=
d=3D
istractible, keep your studio looking like a monk's cell: =3DA0no radio, no=
i=3D
nternet, no visitors. =3DA0Set up the system correctly for your working sty=
le=3D
, and the work will come much more easily. =3DA0(And with that, I need to d=
o =3D
some trimming.)=3D0A=3D0A-Maggie Furtak=3D0A=3D0APate Ceramics=3D0Apatecera=
mics.etsy.=3D
com=3D0Apateceramics.blogspot.com=3D0A781-956-1364=3D0A517 Fellsway East=3D=
0AMalden=3D
, MA 02148
Lee on thu 17 may 12
On Thu, May 17, 2012 at 3:50 PM, John Britt wr=
=3D
ote:
> You know your a potter if: Your pick up truck filled with boxes of pots
> packed in newspaper catches on fire as you are driving to the show.
Or, if you melt your tennis shoes unloading the kiln. Haha!
--
=3DA0Lee Love in Minneapolis
http://mingeisota.blogspot.com/
=3DA0"Ta tIr na n-=3DF3g ar chul an tI=3D97tIr dlainn trina ch=3DE9ile"=3D9=
7that is, =3D
"The
land of eternal youth is behind the house, a beautiful land fluent
within itself." -- John O'Donohue
David Woof on thu 17 may 12
Hi Maggie=3D2C Everyone=3D2C
=3D20
*************************
What with Mike being relatively furless and having opposable thumbs=3D2C it=
m=3D
eans that if you got up early enough you could buy him a wheel borrow and t=
=3D
each him to walk upright and possible some other amusing tricks as well. Wh=
=3D
at a waste of a potentially good hubby to let him and the dog paw around to=
=3D
gether in the cupboards at 5:30 AM!!!! :>} =3D3B>)) <:>)))......triple smil=
es=3D
!!!!
***************************************
As far as being in too much hurry to open a kiln....yes we all must seek to=
=3D
practice and exercise patience strategies.
The strategy I emphasize is for one to comprehend and develop the mind and =
=3D
disciplined character of old time professionalism in all aspects of our wor=
=3D
k=3D2C and of subsequent consequence=3D2C the life we build around it.
One can act professionally in anything one chooses to take to that level. T=
=3D
here is plenty of personal freedom within the realm of professionalism. I j=
=3D
oke some and play some and get myself into and out of all sorts of interest=
=3D
ing situations=3D2C experiences and escapades=3D2C but underneath it all I =
am d=3D
ead serious about my craft=3D2C my art=3D2C and the people I serve.
True professionals aren't such by simply taking the title of such=3D2C or b=
y =3D
acquiring an advanced degree. The professional attitude and hence approach =
=3D
to one's work and our fellow travelers is accessible to all.
There would be far fewer dunky clunky crappy pots=3D2C and failed projects =
so=3D
me are trying to pass off as fine art if more folks aspired to higher achie=
=3D
vement and were willing to stop wanting the quick and easy ready answer or =
=3D
result. The demanding "I want it now with no effort" attitude=3D2C and inve=
st=3D
ed in what is known as paying your dues.
This includes academia=3D2C where playing the game of survival takes a majo=
r =3D
investment over teaching and producing meaningful work that doesn't need th=
=3D
e smoke and mirrors of over intellectualization to validate it.
Some folks are handleing it well=3D2C some not so!!!
It all starts with a desire and developing a disciplined mind. Said anothe=
=3D
r way=3D3B The wealthy aren't wealthy by virtue of their possession of mone=
y =3D
but by possession of the attitude of wealth that makes having wealth a natu=
=3D
ral consequence.
Do have a good day everyone=3D2C
David Woof.....
Exercising discipline by not going for that second Julie's Organic chocolat=
=3D
e covered ice cream bar this AM.
Disclaimer: (I have no vested or personal interest in Julie's=3D2C and hope=
t=3D
hey take no personal interest in me other than to send me a case for free. =
=3D
Oh hell=3D2C reroute me a truck load!!!) put it on my tab. Julie's for ever=
yo=3D
ne!!!
=3D20
P.S. Yippee! I get to open a cooled kiln this AM. No joke=3D2C I really do!=
!!
_________________________________________________________________
5a. Re: Removing pots from a hot kiln
Posted by: "Maggie Furtak" pateceramics@YAHOO.COM
Date: Tue May 15=3D2C 2012 9:45 am ((PDT))
I find the easiest solution to this is to schedule the kiln so that it is c=
=3D
ooling overnight=3D2C and totally cool by the time my furry friend decides =
it=3D
's time for breakfast around 5:30 a.m. That way I'm not tempted to open it =
=3D
too soon=3D2C because I am snoozing away. (By furry friend=3D2C I mean the =
houn=3D
d dog=3D2C not my husband.
Mike is relatively furless and since he has opposable thumbs=3D2C can open =
th=3D
e the cabinet with the people chow in it by himself in the morning). (:
Know thyself! If you are impatient=3D2C set up impatient-ness checks and ba=
la=3D
nces so you don't ruin your good work. If you have blank canvas syndrome an=
=3D
d can't get started=3D2C set up laziness prods=3D2C like putting the coffee=
mak=3D
er in the studio. If you are distractible=3D2C keep your studio looking lik=
e =3D
a monk's cell: no radio=3D2C no internet=3D2C no visitors. Set up the syste=
m co=3D
rrectly for your working style=3D2C and the work will come much more easily=
. =3D
(And with that=3D2C I need to do some trimming.) -
Maggie Furtak =3D
John Britt on thu 17 may 12
You know your a potter if: Your pick up truck filled with boxes of pots=3D2=
0=3D
packed in newspaper catches on fire as you are driving to the show.=3D20
I don't by the professionalism clap trap.
Just get'er done!
John Britt Pottery
John Britt on fri 18 may 12
Lee and Dinah,
Now we are keeping it real!
On Thu, May 17, 2012 at 11:03 PM, wrote:
> Ha ha ha. Did this once when I picked up tankards made for Dianthus by
> Dragon Pottery up in Sheffield, England. The smell of scorching paper as =
we
> sped south down the motorway was quite noticeable. I insisted we close th=
e
> windows so as not to ignite the paper surrounds! God. Bad old days. Don't
> EVER want to repeat all the sturm and drang of deadlines for the Royal
> Shakespeare Theatre. Never.
>
> Dinah
> Mount Vernon, WA.
> www.dinahsnipessteveni.com
> www.dinahsnipessteveni.wordpress.com
> www.etsy.com/shop/DinahSnipesSteveni
> dinahsnipessteveni.tumblr.com
>
>
>
--
Regards,
John
AWESOME VIDEOS: http://www.youtube.com/user/johnbrittpottery
AWESOME BLOG: http://ncclayclub.blogspot.com
WEBPAGE: www.johnbrittpottery.com
jd.steveni@COMCAST.NET on fri 18 may 12
Ha ha ha. Did this once when I picked up tankards made for Dianthus by Drag=
on Pottery up in Sheffield, England. The smell of scorching paper as we spe=
d south down the motorway was quite noticeable. I insisted we close the win=
dows so as not to ignite the paper surrounds! God. Bad old days. Don't EVER=
want to repeat all the sturm and drang of deadlines for the Royal Shakespe=
are Theatre. Never.
Dinah
Mount Vernon, WA.
www.dinahsnipessteveni.com
www.dinahsnipessteveni.wordpress.com
www.etsy.com/shop/DinahSnipesSteveni
dinahsnipessteveni.tumblr.com
Ben Morrison on fri 18 may 12
I haven't caught my truck on fire yet like John apparently did, but I have =
=3D
melted my shoes unloading an anagama before.=3D0A=3D0A=3D0A=3D0A___________=
________=3D
_____________=3D0A From: Lee =3D0ATo: Clayart@LSV.C=
ERAM=3D
ICS.ORG =3D0ASent: Thursday, May 17, 2012 9:21 PM=3D0ASubject: Re: Removing=
pot=3D
s from a hot kiln=3D0A =3D0AOn Thu, May 17, 2012 at 3:50 PM, John Britt hnbr=3D
ittpottery@gmail.com> wrote:=3D0A> You know your a potter if: Your pick up =
tr=3D
uck filled with boxes of pots=3D0A> packed in newspaper catches on fire as =
yo=3D
u are driving to the show.=3D0A=3D0AOr, if you melt your tennis shoes unloa=
ding=3D
the kiln.=3DC2=3DA0 Haha!=3D0A=3D0A--=3D0A=3DC2=3DA0Lee Love in Minneapoli=
s=3D0Ahttp://min=3D
geisota.blogspot.com/=3D0A=3D0A=3DC2=3DA0"Ta tIr na n-=3DC3=3DB3g ar chul a=
n tI=3DE2=3D80=3D
=3D94tIr dlainn trina ch=3DC3=3DA9ile"=3DE2=3D80=3D94that is, "The=3D0Aland=
of eternal yo=3D
uth is behind the house, a beautiful land fluent=3D0Awithin itself." -- Joh=
n =3D
O'Donohue
gina mars on sat 19 may 12
Hi All, Thanks for all the Hot kiln info. I originally asked this =3D
question because
my coworker said reds develop all the way down to 100 degrees. I new =3D
this was not=3D20
true and needed to hear it from someone else. At home I would never =3D
unload a hot kiln
because I am hopefully not in a rush like I am at a school where =3D
everyone is nagging you for their work
that only gets fired once every 4 to 6 weeks.Students are only there for =
=3D
3 hours and they want their work.
We have very few good glazes for cone 6 reduction and I hope Bill works =3D
on a book for them soon.=3D20
As far as the fires in the back of the car, I had that happen once with =3D
raku kiln bricks that were to hot.
Fire in the back seat, not a good thing.
Gina Mars=3D
James Freeman on sat 19 may 12
On Sat, May 19, 2012 at 3:57 PM, John Britt wro=
te:
You can open the kiln any time! Case and point, raku, black seto, or
hikadashi. But you have to have a clay body that can take the thermal
shock.
A few years ago I read about a tile company that fires from room
temperature, up to cone 2, and back to room temperature, in 45 minutes.
The engineer said they could actually do it in 20 minutes, cold, to cone 2,
to cold, but they decided for a reason I can't recall to slow the firing
down to 45 minutes.
...James
James Freeman
"Talk sense to a fool, and he calls you foolish."
-Euripides
http://www.jamesfreemanstudio.com
http://www.flickr.com/photos/jamesfreemanstudio/
http://www.jamesfreemanstudio.com/resources
John Britt on sat 19 may 12
Gina,
Ok.....An average glaze set temperature is around 1300 F . That means=3D20
it usually doesn't change after that no matter what you do. But visually=3D=
20=3D
it may look different, say, look darker in the kiln but when cool it will=
=3D
=3D20
look different (i.e. look fine at room temp). That is why you don't crack=
=3D
=3D20
the kiln at 900 to see if it looks good because you can't read the color=3D=
20=3D
correctly.=3D20
Copper reds are created on the way up, usually between 1500 and 1900=3D20
F but won't show the color until cooled. So if you do draw rings ever hou=
=3D
r=3D20
you won't see color until around 1500 F on the way down. But it is not=3D20=
=3D
created at that temperature, just manifesting.
It is like getting pregnant but not showing until after 6 months and not=3D=
20=3D
giving birth until after 9 months. Same with copper reds. Don't let them=3D=
20=3D
fool you into worrying about the end, it is the beginning that is=3D20
important. Although, striking is reducing on the way down but it is=3D20
unnecessary if you reduce it properly on the way up. (But it can still be=
=3D
=3D20
done with nice effects.)
You can open the kiln any time! Case and point, raku, black seto, or=3D20
hikadashi. But you have to have a clay body that can take the thermal=3D20=
=3D
shock.=3D20
Theoretically, you can open the kiln after 1063 F where quartz inversion=3D=
20=3D
happens but usually since a kiln is a range of temperatures, after 800 F=3D=
20=3D
is best. This will not cause crazing. If the glaze fits the body it won'=
=3D
t=3D20
craze. If the glaze doesn't fit it will accelerate the crazing but not cr=
=3D
eate=3D20
anything that wouldn't happen in 6 months anyway. (delayed crazing)
=3D20
You can get thermal cracking if it is very hot and a wind blows in on a=3D2=
0=3D
pot that is large. So one section of the pot contracts more than say the=3D=
20=3D
foot of the same pot. Not good.=3D20
If you had cristobalite in the clay body you could get cracking around 45=
=3D
0=3D20
F but you probably don't have cristobalite unless you are firing long=3D20
firings like anagama or firing extended periods above 2100 F. (more than=3D=
20=3D
3 - 4 hours.) But with sufficient flux in the clay you won't have to wor=
=3D
ry=3D20
about cristobalite. [and most store bought clays have sufficient flux. Th=
=3D
e=3D20
flux changes the silica/cristobalite (high expansion) to glass (low=3D20
exp./cont. so no cristobalite or not enough to worry about. - e.g=3D20
porcelains have 25% flux so no cristobalite. ]
So, with that said, I try not to open the kiln until it is 400 or so. But=
=3D
=3D20
sometimes even a professional has to do what is necessary. TCB as Elvis=3D2=
0=3D
would say!
I usually open the kiln when I can do it without gloves since hot pots=3D20=
=3D
burn the gloves and you then have to buy new ones. Plus you sweat a=3D20
lot and no one likes that.=3D20
I have done many workshops (over 100) where I am told that the kilns=3D20
can't cool that fast. But the reality is (if you use a pyrometer and make=
=3D
=3D20
readings very hour ) the kiln naturally (meaning all closed up) cools=3D20
about 200 -300 an hour for the first several hours then slows to about=3D20=
=3D
100 - 200 per hour. But usually it is below 1300 F by 5 - 8 hours after i=
=3D
t=3D20
is turned off. Then the damper can be cracked.=3D20
If the kiln goes off at 5 p.m. I can usually open the damper by 11 p.m. I=
=3D
=3D20
will sometimes leave the damper open 1" over night. (although I have=3D20
left it totally open -accidentally -and everything was fine but it was=3D20=
=3D
totally unprofessional.) And in the morning it is 500 F - 600 F (this is =
=3D
in=3D20
a IFB soft brick cone 10 firing - hard brick is longer while electrics an=
=3D
d=3D20
fiber are faster).=3D20
Then I open the damper and crack the door 1" and wait several hours,=3D20
then crack the door 2" , etc. Incidentally, I try not to open a kiln wi=
=3D
th a=3D20
metal frame (sprung arch) when it is too hot because that stresses out=3D2=
0=3D
the metal frame. (corrodes and weakens it)=3D20=3D20
Then kiln can then be unloaded after 200 - 300 F.
Just my opinion/experience, which should not be believed, but which is=3D20=
=3D
=3D20
hopefully based on scientific principles and thus reproducible, although =
=3D
I=3D20
have been wrong in the past thus will probably be wrong again so ...you=3D2=
0=3D
should probably read and think for yourself! In short, don't do what I do=
=3D
!
John Britt Pottery
Randall Moody on sat 19 may 12
I have found that if I let the kiln cool to less than 100 degrees I get
much less crazing across all of my glazes. It may be argued by some that
crazing isn't affected by this but rather the glaze fit to the body but I
can't argue with seeing the results.
--
Randall in Atlanta
http://wrandallmoody.com
Robert Harris on sun 20 may 12
In this case you're just delaying the crazing. Stick the pots in
boiling water a couple of times (or wait for six months), and all that
extra crazing will appear.
Robert
On Sat, May 19, 2012 at 9:14 PM, Randall Moody wr=
ote:
> I have found that if I let the kiln cool to less than 100 degrees I get
> much less crazing across all of my glazes. It may be argued by some that
> crazing isn't affected by this but rather the glaze fit to the body but I
> can't argue with seeing the results.
>
> --
> Randall in Atlanta
> http://wrandallmoody.com
--
----------------------------------------------------------
Randall Moody on sun 20 may 12
I do have to say that I haven't boiled my pots but after six months of use
for coffee I haven't found any crazing. Not that a little crazing bothers
me all that much.
On Sun, May 20, 2012 at 3:35 PM, Robert Harris wro=
te:
> In this case you're just delaying the crazing. Stick the pots in
> boiling water a couple of times (or wait for six months), and all that
> extra crazing will appear.
>
>
> Robert
>
>
> On Sat, May 19, 2012 at 9:14 PM, Randall Moody
> wrote:
> > I have found that if I let the kiln cool to less than 100 degrees I get
> > much less crazing across all of my glazes. It may be argued by some tha=
t
> > crazing isn't affected by this but rather the glaze fit to the body but=
I
> > can't argue with seeing the results.
> >
> > --
> > Randall in Atlanta
> > http://wrandallmoody.com
>
>
>
> --
> ----------------------------------------------------------
>
--
Randall in Atlanta
http://wrandallmoody.com
| |
|
