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help with new kiln

updated thu 24 apr 03

 

Earl Brunner on tue 22 apr 03


Do you have your electric service matched to the kiln requirements
correctly? Correct voltage? Correct Phase power? You need to tell us
more abut the kiln. Name the brand; you really need to do that if you
REALLY want help, and apparently the manufacturer isn't being much
help....

The "opinions" of the person that you talked to regarding the vent and
fumes is clearly wrong. If their kiln was under-engineered then venting
could be a problem, but it SHOULDN'T.

-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of Cindy Gatto
Sent: Tuesday, April 22, 2003 11:55 AM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Help with new kiln

Hello All:
We recently purchased an 11.9 cu.ft. mid size oval kiln,
we
are choosing not to mention the brand for reasons that will become clear
further in the post. First we have problems with the firing cycle, when
starting the kiln on low I cannot get any temperature rise or color in
the
kiln no matter how long it is left on. When going to medium it is the
same
situation no temp climb no color in the kiln. I cannot get any color or
temp
rise until all switches are on high. This being so my firing cycle is
Luke
warm then a fast rise in temperature. We are not getting proper melt in
the
matte glazes, they are very dry and sand like to the touch basically
they
look like crap almost as if they are under fired but the witness cones
say
different. The gloss glazes look O.K. from a technical standpoint, the
colors
don't seem to look as "pretty" they look kinda muddy, but they look
properly
fired. It also takes approx. 24 to 26 hours to go to cone six.
So after four or so firings we decided to call the manufacturer,
we
are thinking there is something wrong with the kiln especially because
of the
low and medium no temp/no color situation. We were told that that is
normal
the we are not going to get any kinda temp or color on low or medium and
that
we should even shorten the times on low and medium. Which means we will
be
going from an even colder kiln straight to high. Everything I have ever
been
taught or read says this is wrong.
Also upon telling this technician that we have an Orton down
draft
kiln vent on our kiln he told us that they are useless. He also says
that the
vent draws an enormous amount of heat out of the kiln. He told us that
the
kiln vent does nothing but cause problems and that we do not need a vent
at
all. He says that we could never get anything toxic coming out of the
kiln.
No matter what we fire there is nothing coming out of the kiln that
would be
toxic. Again everything we have ever been told or read says that this is
not
true.
As you can see we are getting mixed information here and now we
are
not sure what the hell to do. Is there something wrong with our new kiln
or
do we just need to adjust our way of firing?
Any help would be greatly appreciated.
Thank you in advance for any help.
Cindy & Mark
The Mudpit
228 Manhattan Ave
Brooklyn NY 11206
718-218-9424
mudpitnyc@aol.com
www.mudpitnyc.com

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Cindy Gatto on tue 22 apr 03


Hello All:
We recently purchased an 11.9 cu.ft. mid size oval kiln, we
are choosing not to mention the brand for reasons that will become clear
further in the post. First we have problems with the firing cycle, when
starting the kiln on low I cannot get any temperature rise or color in the
kiln no matter how long it is left on. When going to medium it is the same
situation no temp climb no color in the kiln. I cannot get any color or temp
rise until all switches are on high. This being so my firing cycle is Luke
warm then a fast rise in temperature. We are not getting proper melt in the
matte glazes, they are very dry and sand like to the touch basically they
look like crap almost as if they are under fired but the witness cones say
different. The gloss glazes look O.K. from a technical standpoint, the colors
don't seem to look as "pretty" they look kinda muddy, but they look properly
fired. It also takes approx. 24 to 26 hours to go to cone six.
So after four or so firings we decided to call the manufacturer, we
are thinking there is something wrong with the kiln especially because of the
low and medium no temp/no color situation. We were told that that is normal
the we are not going to get any kinda temp or color on low or medium and that
we should even shorten the times on low and medium. Which means we will be
going from an even colder kiln straight to high. Everything I have ever been
taught or read says this is wrong.
Also upon telling this technician that we have an Orton down draft
kiln vent on our kiln he told us that they are useless. He also says that the
vent draws an enormous amount of heat out of the kiln. He told us that the
kiln vent does nothing but cause problems and that we do not need a vent at
all. He says that we could never get anything toxic coming out of the kiln.
No matter what we fire there is nothing coming out of the kiln that would be
toxic. Again everything we have ever been told or read says that this is not
true.
As you can see we are getting mixed information here and now we are
not sure what the hell to do. Is there something wrong with our new kiln or
do we just need to adjust our way of firing?
Any help would be greatly appreciated.
Thank you in advance for any help.
Cindy & Mark
The Mudpit
228 Manhattan Ave
Brooklyn NY 11206
718-218-9424
mudpitnyc@aol.com
www.mudpitnyc.com

rob on tue 22 apr 03


Mark and Cindy:

It seems you not only need help with your kiln, but with your manufacturer
as well. Whoever told you that there should be no temperature rise when the
kiln is set to low or medium is wrong; if I want a longer firing cycle,
sometimes neccessary with the new glazes I have been experimenting with, I
fire the kiln on low for 2 hours and the turn it to medium for the
remainder. It reaches Cone 6 in about 10 hours that way, as opposed to 6-7
for a kick up to "high" after 2 hours.

Some more information is neccessary, though. Is this a manually fired kiln,
or does it have an electric controller?

As to the kiln vent, I am not a big proponent of the downdraft models, but I
have never heard of them making a large difference in temperature. And
again, your supplier is lying to you here; some jurisdictions require kilns
in public spaces (like art centers) to be vented. Furthermore, if you fire
lusters, or certain types of glazes, then yes, you will release toxic
emmisions into the kiln room. Venting will help eliminate this.


Rob Van Rens
-at Pine Ridge Pottery Supply in Alexandria, VA

----- Original Message -----
From: "Cindy Gatto"
To:
Sent: Tuesday, April 22, 2003 2:54 PM
Subject: Help with new kiln


> Hello All:
> We recently purchased an 11.9 cu.ft. mid size oval kiln,
we
> are choosing not to mention the brand for reasons that will become clear
> further in the post. First we have problems with the firing cycle, when
> starting the kiln on low I cannot get any temperature rise or color in the
> kiln no matter how long it is left on. When going to medium it is the same
> situation no temp climb no color in the kiln. I cannot get any color or
temp
> rise until all switches are on high. This being so my firing cycle is Luke
> warm then a fast rise in temperature. We are not getting proper melt in
the
> matte glazes, they are very dry and sand like to the touch basically they
> look like crap almost as if they are under fired but the witness cones say
> different. The gloss glazes look O.K. from a technical standpoint, the
colors
> don't seem to look as "pretty" they look kinda muddy, but they look
properly
> fired. It also takes approx. 24 to 26 hours to go to cone six.
> So after four or so firings we decided to call the manufacturer, we
> are thinking there is something wrong with the kiln especially because of
the
> low and medium no temp/no color situation. We were told that that is
normal
> the we are not going to get any kinda temp or color on low or medium and
that
> we should even shorten the times on low and medium. Which means we will be
> going from an even colder kiln straight to high. Everything I have ever
been
> taught or read says this is wrong.
> Also upon telling this technician that we have an Orton down draft
> kiln vent on our kiln he told us that they are useless. He also says that
the
> vent draws an enormous amount of heat out of the kiln. He told us that
the
> kiln vent does nothing but cause problems and that we do not need a vent
at
> all. He says that we could never get anything toxic coming out of the
kiln.
> No matter what we fire there is nothing coming out of the kiln that would
be
> toxic. Again everything we have ever been told or read says that this is
not
> true.
> As you can see we are getting mixed information here and now we are
> not sure what the hell to do. Is there something wrong with our new kiln
or
> do we just need to adjust our way of firing?
> Any help would be greatly appreciated.
> Thank you in advance for any help.
> Cindy & Mark
> The Mudpit
> 228 Manhattan Ave
> Brooklyn NY 11206
> 718-218-9424
> mudpitnyc@aol.com
> www.mudpitnyc.com
>
>
____________________________________________________________________________
__
> 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.
>

Arnold Howard on tue 22 apr 03


Cindy, it is possible that the kiln person you spoke to is new at the
job. It is difficult for an employer to keep track of everything a new
customer service person tells the customer.

It sounds like your kiln was mis-wired in some way. Do you have a local
technician who can visually trace the wiring and compare it to the
correct wiring diagram?

The Orton down-draft vent removes only a small amount of heat from the
kiln. It doesn't appreciably change the firing time.

Sincerely,

Arnold Howard
Paragon

From: Cindy Gatto
> We recently purchased an 11.9 cu.ft. mid size oval
kiln, we
> are choosing not to mention the brand for reasons that will become
clear
> further in the post. First we have problems with the firing cycle,
when
> starting the kiln on low I cannot get any temperature rise or color in
the
> kiln no matter how long it is left on. When going to medium it is the
same
> situation no temp climb no color in the kiln. I cannot get any color
or temp
> rise until all switches are on high. This being so my firing cycle is
Luke
> warm then a fast rise in temperature. We are not getting proper melt
in the
> matte glazes, they are very dry and sand like to the touch basically
they
> look like crap almost as if they are under fired but the witness cones
say
> different. The gloss glazes look O.K. from a technical standpoint, the
colors
> don't seem to look as "pretty" they look kinda muddy, but they look
properly
> fired. It also takes approx. 24 to 26 hours to go to cone six.
> So after four or so firings we decided to call the
manufacturer, we
> are thinking there is something wrong with the kiln especially because
of the
> low and medium no temp/no color situation. We were told that that is
normal
> the we are not going to get any kinda temp or color on low or medium
and that
> we should even shorten the times on low and medium. Which means we
will be
> going from an even colder kiln straight to high. Everything I have
ever been
> taught or read says this is wrong.
> Also upon telling this technician that we have an Orton down
draft
> kiln vent on our kiln he told us that they are useless. He also says
that the
> vent draws an enormous amount of heat out of the kiln. He told us
that the
> kiln vent does nothing but cause problems and that we do not need a
vent at
> all. He says that we could never get anything toxic coming out of the
kiln.
> No matter what we fire there is nothing coming out of the kiln that
would be
> toxic. Again everything we have ever been told or read says that this
is not
> true.
> As you can see we are getting mixed information here and now we
are
> not sure what the hell to do. Is there something wrong with our new
kiln or
> do we just need to adjust our way of firing?
> Any help would be greatly appreciated.
> Thank you in advance for any help.
> Cindy & Mark

william schran on tue 22 apr 03


Cindy & Mark wrote about problems increasing temperatures in their
new oval kiln when the switches are on low or medium & manufacturer
saying kiln vent was a waste and no toxics coming from kiln.

BULLS**T!

Anytime something is heated and "burns" carbon monoxide is released.
That's one good reason to have the kiln vent. Certainly there are
other organics that will burn out also. Use the Vent!

First thought would be to check the voltage you're getting to the
kiln. A kiln with 240V elements will take a long time to reach
temperature if the kiln is only fed 208V. Is the line coming to the
kiln big enough? Is it getting hot to the touch? Might need bigger
wiring.

Just a couple of thoughts to start with.
Bill

Gary Lee on tue 22 apr 03


Hi guys

Someone mentioned that your power coming into the kiln may be wrong.
Correct! Start there. You need 240v @48 amps to power that kiln at the
kiln. Right? Make sure you have at least a 100 amp circuit coming into the
breaker at the kiln. Use a 60 amp breaker at that point. Make sure the
wiring from the main breaker to the kiln breaker is the proper
size............... Depends on the distance. You should be able to go all
LOW for 2 hours and get good heat but you probably will not get color until
you get to all MED. You can then go to MED for 1 hour. All HIGH should fire
off cone 6 in about 5-6 hours.

Always use a vent system unless your kiln is outside in an open shed. All
glazes will off gas. No vent and they will off gas into your kiln room or
studio. Leave your vent off one firing and go into the room and take a good
whiff as you turn up from MED to HIGH. You will see what I am talking about.
You can receive "heavy metal poisoning" from these gases if you breathe
enough and it does not take much. Anyone telling you different is just plain
"wrong" and should not be working for any kiln maker. I would recommend you
talk to the "boss/owner" of this kiln maker and explain what you have wrote
here and see what they have to say. In fact, let everyone here know so we
can avoid this particular maker. Before they get someone hurt or killed with
their "wrong" information.