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loading bisque

updated mon 27 nov 06

 

Lisa E on thu 23 nov 06


Hello Again Clayarters!

If all goes well I will have my kiln up and running this weekend!!! I am
soooo excited.

I have heard conflicting things are loading up a kiln for a bisque firing.
I have heard the fuller it is, the better it will hold the heat. I realize
the temp should be brought up slowly in this case.

Also some people say stacking is not a problem as long as all the weight
is on the foot of the pieces below and not on the rims. Is that true? Can
I stack? If so, how much is safe?

My kiln has a small 18" interior and being a newbie some of my work is thick
so I am wondering if stacking is such a good idea.

Any feedback would be appreciated!

Regards,
--
Lisa E
Sunny Daze Design Pottery Studio
Squamish, BC

William & Susan Schran User on thu 23 nov 06


On 11/23/06 12:25 PM, "Lisa E" wrote:

> Also some people say stacking is not a problem as long as all the weight
> is on the foot of the pieces below and not on the rims. Is that true? Can
> I stack? If so, how much is safe?

Stacking lip to lip, foot to foot is fine as long as the weight is not too
great. Stacking bowls inside each other is also fine as long as the foot of
the one nesting inside is sitting on the foot area of the one below.

I've stacked cups 6 or 7 high with no problems.

The furniture in the kiln will actually take more energy to heat and will
hold heat longer than the pots.


--
William "Bill" Schran
wschran@cox.net
wschran@nvcc.edu
http://www.creativecreekartisans.com

Lisa E on fri 24 nov 06


Thank you all for your feedback and advice. It is very helpful! Lisa

On 11/23/06, William & Susan Schran User wrote:
>
> On 11/23/06 12:25 PM, "Lisa E" wrote:
>
> > Also some people say stacking is not a problem as long as all the weight
> > is on the foot of the pieces below and not on the rims. Is that
> true? Can
> > I stack? If so, how much is safe?
>
> Stacking lip to lip, foot to foot is fine as long as the weight is not too
> great. Stacking bowls inside each other is also fine as long as the foot
> of
> the one nesting inside is sitting on the foot area of the one below.
>
> I've stacked cups 6 or 7 high with no problems.
>
> The furniture in the kiln will actually take more energy to heat and will
> hold heat longer than the pots.
>
>
> --
> William "Bill" Schran
> wschran@cox.net
> wschran@nvcc.edu
> http://www.creativecreekartisans.com
>
>
> ______________________________________________________________________________
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
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>
> Moderator of the list is Mel Jacobson who may be reached at
> melpots@pclink.com.
>



--
Lisa E
Sunny Daze Design Pottery Studio
Squamish, BC

jsmola on fri 24 nov 06


Lisa--


You can certainly stack pieces within pieces when doing a bisque fire--that
is no problem if you follow the guide lines you've been given. However, as a
"newbie" (how about a 'budding artist') and some of the items are thick--I
would recommend you not stack items at first. If there are any air pockets;
or moisture that you may still be residing in a thicker piece--it could
result in broken pieces, and not just one piece but anything that is stacked
together. Good luck!

Jaymes
The Pottery Pimp

-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of Lisa E
Sent: Thursday, November 23, 2006 12:26 PM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Loading Bisque

Hello Again Clayarters!

If all goes well I will have my kiln up and running this weekend!!! I am
soooo excited.

I have heard conflicting things are loading up a kiln for a bisque firing.
I have heard the fuller it is, the better it will hold the heat. I realize
the temp should be brought up slowly in this case.

Also some people say stacking is not a problem as long as all the weight is
on the foot of the pieces below and not on the rims. Is that true? Can I
stack? If so, how much is safe?

My kiln has a small 18" interior and being a newbie some of my work is thick
so I am wondering if stacking is such a good idea.

Any feedback would be appreciated!

Regards,
--
Lisa E
Sunny Daze Design Pottery Studio
Squamish, BC

____________________________________________________________________________
__
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.



Jaymes
The Pottery Pimp

Ed Bull on sat 25 nov 06


Lisa,
A few thoughts:
Use a good kiln wash, multiple very thin coats, let dry between each.
Try to use taller posts on the bottom to get two elements heating there.
Rim to rim or foot to foot on lighter pieces if you stack.
Let those heavy ones dry for a good long time before you bisque 'em.
If they explode vacuum safely and use a dental pick to get all the
chunks out from between the elements.
If you fire flat things with smaller posts, make sure
you have an element on that course.
Floss.
Dance.
Try not to get a kiln shelf directly next to the elements.
Keep your kiln nice and clean.
Don't let any glaze get onto the elements.
Vent it well.
Happy firing.
Cheers,
Ed Bull
www.creativeclaypottery.com

Ron Roy on sat 25 nov 06


Stacking pots in a bisque firing can also be a problem depending on the
type of clay used.

Iron bearing clay may be affected in such a way as to turn the iron into a
flux if there is not enough oxygen to help combust all the carbon.

Making sure the firing is slow enough and there is enough oxygen to
facilitate burning of all organics is the answer if problems with pinholing
occur.

If there is some reduction of iron in pots that are stacked rim to rim - I
would expect to see more pin holes inside the ware due to trapped carbon in
the bisque firing for instance.

RR


>> Also some people say stacking is not a problem as long as all the weight
>> is on the foot of the pieces below and not on the rims. Is that true? Can
>> I stack? If so, how much is safe?
>
>Stacking lip to lip, foot to foot is fine as long as the weight is not too
>great. Stacking bowls inside each other is also fine as long as the foot of
>the one nesting inside is sitting on the foot area of the one below.
>
>I've stacked cups 6 or 7 high with no problems.
>
>The furniture in the kiln will actually take more energy to heat and will
>hold heat longer than the pots.

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

Snail Scott on sat 25 nov 06


At 09:25 AM 11/23/2006 -0800, you wrote:
>I have heard conflicting things are loading up a kiln for a bisque firing.
>I have heard the fuller it is, the better it will hold the heat. I realize
>the temp should be brought up slowly in this case.


'Holding heat' is a kinda silly term.
It might be relevant in a fuel-fired
kiln where heat and air movement are very
important and a too-empty kiln may not
sufficiently impede the throughput of
the heat. For an electric kiln it
makes no real sense, except to the extent
that a full kiln creates a b it of a
built-in 'soak cycle' and slower cool.
Neither of those is relevant to bisque
firing, though. The heat that is 'held'
still has to pumped into the stuff to
begin with. It does tend to be more
economical to fire a big load than a
small one, but the difference isn't huge.

>Also some people say stacking is not a problem as long as all the weight
>is on the foot of the pieces below and not on the rims. Is that true? Can
>I stack? If so, how much is safe?

It depends on the fragility of the work.
You need to use your judgement as to
the strength of the work on the bottom.

>...some of my work is thick
>so I am wondering if stacking is such a good idea.

If it's thick, it's safer. It's breakage
that we're mainly concerned about. Now,
if you have a lot of plates or tiles that
might get stacked flat on each other,
the stuff at the bottom may not burn out
as well, since it's as though the stuff
at the bottom was as thick as the whole
stack. That will require a longer firing,
to get really good burnout. If you leave
even a small air gap, though, it will be
fine. And don't let things 'nest' really
tightly. As they expand and shrink during
heating and cooling, they might 'bind'
a bit and crack.

Good luck!

-Snail