search  current discussion  categories  kilns & firing - misc 

electric kiln question

updated thu 18 aug 11

 

Burtt on mon 27 sep 99

Just bought a new Paragon kiln with a computer. I wanted just a kiln
sitter, but they didn't have one in stock, and I didn't want to wait. So
far, I'm very happy with the computer assisted system.
But it has a function for holding or ``soaking'' at the end of the
firing. Can someone tell me when you soak, why you soak and how long you
soak? The instruction book tells me what the function is, but not why I
need the function.
Thanks.

Steve Burtt
Ocean Springs, Mississippi, where we've had a beautiful fall week...but
it's starting to warm up again.

Cindy Romanski on tue 24 oct 00


I work at a pottery and have a question about our electric Olympic kilns.
The models vary since we purchased them at different times but they are all
octogon and some have computers on the kiln and some are mounted on the
wall, we also have several without computers. We have seven of them and the
plugs between sections burn out on a regular basis, almost daily. Since we
are firing them to ^10 every other firing I do expect alot of wear and tear.
Here's my question: I was wondering if it would do any harm to hard wire
the sections together? Since, we will probably not be moving them for a very
long time and it takes so much time to replace the plug each time, not
including the cost of those plugs. Can I do this and get away without
damaging anything? I've gone through this in my mind and can't seem to come
up with a reason why I couldn't but, I would love some other opinions on
this. Another question: Could I put some Kaowool in the boxes between the
kiln and the wiring to protect the wiring from getting so much heat?
We have just purchased a gas kiln and are starting to do some of our ^10
firings in it but, it will be awhile till it is in full production.

Thanks in advance,
Cindy Romanski
Chilmark Pottery
Martha's Vineyard, MA

_________________________________________________________________________
Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com.

Share information about yourself, create your own public profile at
http://profiles.msn.com.

Snail Scott on tue 24 oct 00


Cindy-

Hardwiring is a pretty good idea - those connectors are
notoriously squirrely. I wouldn't put kaowool in the boxes, though;
they're kept open and vented for a reason.

-Snail


At 01:41 PM 10/24/00 GMT, you wrote:
>I work at a pottery and have a question about our electric Olympic kilns.
>The models vary since we purchased them at different times but they are all
>octogon and some have computers on the kiln and some are mounted on the
>wall, we also have several without computers. We have seven of them and the
>plugs between sections burn out on a regular basis, almost daily. Since we
>are firing them to ^10 every other firing I do expect alot of wear and tear.
> Here's my question: I was wondering if it would do any harm to hard wire
>the sections together? Since, we will probably not be moving them for a very
>long time and it takes so much time to replace the plug each time, not
>including the cost of those plugs. Can I do this and get away without
>damaging anything? I've gone through this in my mind and can't seem to come
>up with a reason why I couldn't but, I would love some other opinions on
>this. Another question: Could I put some Kaowool in the boxes between the
>kiln and the wiring to protect the wiring from getting so much heat?
>We have just purchased a gas kiln and are starting to do some of our ^10
>firings in it but, it will be awhile till it is in full production.
>
>Thanks in advance,
>Cindy Romanski
>Chilmark Pottery
>Martha's Vineyard, MA
>

Snail Scott on tue 24 oct 00


Cindy-

I was a little irresponsible in my previous post. Although many
kilns are hardwired, thus eliminating the tendency of those darn
connectors to fry themselves, they shouldn't be frying themselves
_quite_ that often! If they have too much 'juice' running through
them, then they might be acting like accidental circuit breakers,
and hardwiring the sections together would cure the symptom, not
the disease, which might get worse undetected, pending disaster.
Get the amperage checked first! Any electrician-type can do this
easily. (Curiosity question-do they burn out when you've just
turned up the heat to the next level, or after it's been at that
level for a while? Amperage tends to spike just after a turnup,
then drops off as the elements heat up and resistance decreases.)


At 08:59 AM 10/24/00 -0700, I wrote:
>Cindy-
>
>Hardwiring is a pretty good idea - those connectors are
>notoriously squirrely. I wouldn't put kaowool in the boxes, though;
>they're kept open and vented for a reason.
>
> -Snail
>
>
>At 01:41 PM 10/24/00 GMT, you wrote:
>>I work at a pottery and have a question about our electric Olympic kilns.
>>The models vary since we purchased them at different times but they are all
>>octogon and some have computers on the kiln and some are mounted on the
>>wall, we also have several without computers. We have seven of them and the
>>plugs between sections burn out on a regular basis, almost daily. Since we
>>are firing them to ^10 every other firing I do expect alot of wear and tear.
>> Here's my question: I was wondering if it would do any harm to hard wire
>>the sections together? Since, we will probably not be moving them for a very
>>long time and it takes so much time to replace the plug each time, not
>>including the cost of those plugs. Can I do this and get away without
>>damaging anything? I've gone through this in my mind and can't seem to come
>>up with a reason why I couldn't but, I would love some other opinions on
>>this. Another question: Could I put some Kaowool in the boxes between the
>>kiln and the wiring to protect the wiring from getting so much heat?
>>We have just purchased a gas kiln and are starting to do some of our ^10
>>firings in it but, it will be awhile till it is in full production.
>>
>>Thanks in advance,
>>Cindy Romanski
>>Chilmark Pottery
>>Martha's Vineyard, MA
>>
>
>___________________________________________________________________________
___
>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.
>

Craig Martell on tue 24 oct 00


Hi:

I had one of Olympics 16 cu ft oval kilns that was made when they were
still in Washington state. It was a very poorly engineered kiln in my
opinion and I totally rebuilt the kiln. One of the things I did was hard
wire the interbox plugs. The flexing and movement of the kiln body during
heating and cooling will cause these interbox plugs to move and eventually
loosen and lose electrical potential due to bad contact between the male
and female connections. This causes heat and burnout. SO....., yes,
hardwiring these connections is a good idea. Just be certain to insulate
the joins well. Use bolt connectors and hi temp insulation.

regards, Craig Martell in Oregon

Alisa and Claus Clausen on wed 25 oct 00


Dear Cindy,
One of errors we made when rebuilding and rewiring my 30 year old =
electric kiln, was to insulate too well. The back
of the kiln got a good layer of high heat insulation and the connectors =
burned out all the time. We removed the
extra, extra insulation and it is firing as it should. This is nothing =
specific of what to or not to do (wow, what a help)
just a suggestion to get an expert opinion about the boxes.

Best regards,
Alisa

Gavin Stairs on wed 25 oct 00


At 02:58 PM 10/25/00, Alisa wrote:
>Dear Cindy,
>One of errors we made when rebuilding and rewiring my 30 year old electric
>kiln, was to insulate too well. The back
>of the kiln got a good layer of high heat insulation and the connectors
>burned out all the time. We removed the
>extra, extra insulation and it is firing as it should. This is nothing
>specific of what to or not to do (wow, what a help)
>just a suggestion to get an expert opinion about the boxes.

Yes, I'm glad you wrote this, Alisa. It is one of the problems of kiln
insulation design that because the inside is so hot, and because low
temperature insulation is so much better than high temperature insulation
(it has to do with radiative transfer across air gaps--bridging), it is
difficult to include much metal structure inside the insulation layers. If
you go even an inch below some fibre, the temperature tends to be too hot
for most ordinary metals like steel, aluminum and brass. Even most
stainless steels. So, this can mean trouble for add-on insulation around
an electric kiln. What Alisa is pointing out is that it is particularly
hard on the electrical connectors, which are already trouble spots for
overheating, because they conduct heat from the inside to the outside,
creating a local hot-spot just where you don't want one. If you are trying
to increase the insulation by wrapping around an old kiln, don't put on too
much, and leave a nice big bare patch beside the terminals. Also, don't
block the space between the control box and the kiln. Space it away so
there's at least as much space between as there was before you
re-insulated. And, if you are including the old metal skin under the
blanket, be aware that it may overheat and begin to disintegrate or
warp. If this is what holds the lid on, you may have some trouble down the
road. Also, most lids and floors are kept in one piece by a compression
band around the edge. If this is buried under the insulation too much, it
may relax and let the lid/floor begin to crack.

Electric kilns are under-insulated for the most part, but increasing the
insulation is more troublesome that just adding a blanket.

Gavin


Gavin Stairs
Stairs Small Systems
921 College St., # 1-A
Toronto, Ontario, Canada M6H 1A1
phone: (416)530-0419 stairs@stairs.on.ca

Claudia MacPhee on tue 16 aug 11


An ancient Cress electric kiln has come into my hands. It looks like par=
=3D
ts of the kiln sitter are missing. Can I fire this thing with my pyrometer/=
=3D
cones ? Do you need to set a kiln sitter for it to work? The only time I ha=
=3D
ve used electric kilns they have had a working kiln sitter or else a contro=
=3D
ller.
This guy had two manual controls. No timer.=3D20

thanks for any answers.

Claudia MacPhee Tagish=3D2C Yukon

Fired off my wood kiln on Sunday=3D2C impatiently waiting to open.......

=3D

David Woof on wed 17 aug 11


Hi Claudia=3D2C

I assume the sitter is a Dawson. You don't specify which parts are missing=
=3D
=3D20
so this is a shot in the dark. Lots of "ifs" controlled by assumptions.=3D2=
0
You will need to repair=3D2C rig up=3D2C or bypass the sitter if you wish t=
o fi=3D
re with cones. =3D20

It is possible to rig the exterior works if the activation push button stil=
=3D
l engages and=3D20
closes the electrical circuit.
You will have to manually trip it off by pushing a wee protrusion that woul=
=3D
d be normally hit
by the drop mechanism when/if the drop mechanism was/is still there.=3D20
However if interior parts are missing...is this getting "clear as mud"?
=3DA0
It would be best to stop here and encourage you to find a local potter to=
=3D20
come and diagnose for you.

If you find a qualified person to do this next stunt=3D3B it is possible to=
r=3D
e wire a by-pass=3D20
past the sitter so the rest of your controls can still do their job.

If the kiln is ancient and much used=3D2C the elements may be at the cookie=
b=3D
aking stage of life
and you are looking at several hundred dollars(US)to replace. Are the brick=
=3D
s=3D2C element groves=3D2C
and lid in good shape? Get the elements tested before anymore time and mone=
=3D
y spent.=3D20
Decisions to make!

Always a good second choice is to cut a hole(s) in the bottom of the wall f=
=3D
or a Raku gas burner=3D20
conversion.

Some years ago I built a 3'X 3'X 3'cube IFB gas kiln that I can stack four =
=3D
9"X 35" old=3D20
electric kiln rings with an exhaust cutout in the lid to make it an updraft=
=3D
=3D20
capable of firing a 5 foot tall sculpture=3D2C or short firing the cube to =
co=3D
ne 10/11.=3D20
I also have a side door for Glass mold casting and hot glass manipulation.=
=3D
=3D20

Sorta crude=3D2C but gets several jobs done well.=3D20

Annealing is a bit of a dance=3D2C but I do like to dance.

David Woof

P.S.=3D20

Don't rely on the pyrometer.=3D20
It is not God's holy word of kiln and glaze firing. It is more of a Devil a=
=3D
nd Satan.
It will lie to you=3D2C raise false hopes and ruin your glazes and your lif=
e =3D
if you listen to it. =3D20
A pyrometer at best will show you the progression of heat rise but does not=
=3D
=3D20
give accurate readings unless periodically recalibrated=3D2C and indicates =
no=3D
thing about=3D20
"heat work"=3D2C which is the explanation and means for glaze maturation in=
t=3D
he firing.=3D20
__________________________________

Date: Tue=3D2C 16 Aug 2011 10:42:48 -0700
From: Claudia MacPhee
Subject: Electric Kiln Question
=3D20
An ancient Cress electric kiln has come into my hands. It looks like par=
=3D
=3D3D
ts of the kiln sitter are missing. Can I fire this thing with my pyrometer/=
=3D
=3D3D
cones ? Do you need to set a kiln sitter for it to work? The only time I ha=
=3D
=3D3D
ve used electric kilns they have had a working kiln sitter or else a contro=
=3D
=3D3D
ller.
This guy had two manual controls. No timer.=3D3D20
=3D20
thanks for any answers.
=3D20
Claudia MacPhee Tagish=3D3D2C Yukon
=3D20
Fired off my wood kiln on Sunday=3D3D2C impatiently waiting to open.......
=3D20




=3D

Rogier Donker on wed 17 aug 11


Hey Claudia,
Yes you can fire the kiln with just the pyrometer
and cones, but I would urge you to be PRESENT when doing so! Seems to
me you are another potential customer for my kiln manual.... see the
website!
Rogier

P.S. See us on the web at http://www.donkerstudio.org

Arnold Howard on wed 17 aug 11


On 8/16/2011 12:42 PM, Claudia MacPhee wrote:
An ancient Cress electric kiln has come into my hands. It looks like
parts of the kiln sitter are missing. Can I fire this thing with my
pyrometer/cones ? Do you need to set a kiln sitter for it to work?

If your kiln is in sound condition and the Kiln Sitter needs only a new
porcelain tube, rod, or cone supports, I would repair the Kiln Sitter.

Sincerely,

Arnold Howard
Paragon Industries, L.P., Mesquite, Texas USA
ahoward@paragonweb.com / www.paragonweb.com