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how to see the witness cones

updated thu 6 jun 02

 

CTaylor174@AOL.COM on sun 2 jun 02


I have always had a problem seeing the cones in both my small and large
electric kiln. Then I remembered something I had heard at a workshop years
ago. So long ago that I do not remember where it came from. I now put a
thin line of red iron oxide on each edge of the cones and have absolutely no
trouble seeing the cones, even without a safety glass.

Hope that this idea might help.

Chris Taylor

Bacia Edelman on sun 2 jun 02


Some years ago, I phoned a troubleshooter at Orton Cone Co.
and he told me that the iron oxide affected the melt of the
cones. I therefore abided by his advice and now have
some trouble again seeing the cones in elec. kilns unless there
is a clear sight line to the rear of kiln and one can see
the elements beyond the cone pack. That is not always possible to
achieve.
Bacia

At 03:57 AM 06/02/2002 EDT, you wrote:
>I have always had a problem seeing the cones in both my small and large
>electric kiln. Then I remembered something I had heard at a workshop years
>ago. So long ago that I do not remember where it came from. I now put a
>thin line of red iron oxide on each edge of the cones and have absolutely
no
>trouble seeing the cones, even without a safety glass.
>
>Hope that this idea might help.
>
>Chris Taylor
>
>___________________________________________________________________________
___
>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.
>



Bacia Edelman Madison, Wisconsin
http://users.skynet.be/russel.fouts/bacia.htm
http://www.silverhawk5.com/edelman/index.html

Tommy Humphries on sun 2 jun 02


Viewing the cones in an electric kiln can be a PITA if proper procedures are
not followed. Common sense would have you putting the cones close to the
peepholes for the best view. HOWEVER...most peeps have a conical shape to
them, which allows a really wide field of view as long as you put the cones
AWAY from the peepholes. Put the cones on the edge of the shelf directly in
front of the peep, and you will only see part of the cone pack...no matter
what you do. I always put the cones at least to the center of the shelf,
this not only allows for a full view of the cones from the peep, but insures
an accurate measurement of the heat in the center of the kiln.

Also if possible, set taller pieces on the shelf where the cones are, and
raise the cones on a short post...load short, or flat pots in front and
behind the cones, so that you have a clear view past the cones to the
elements. This is the absolute best way to actually see the cones, without
introducing air, or whatever to cool the conepack a bit, which is a serious
no-no.

Now for a question...when you open a peephole in an electric kiln, cold air
will enter the kiln, especially if there is a vent going...this cold air
forms a "bubble" around the peephole. Is it my imagination or is there a
slight magnification of objects away from the peephole, due to the denser
cold air? It always seems that I can see the most minute details of the
bricks and elements opposite the peeps...could be another reason to position
the cones away from the peeps...magnification!

Tommy


----- Original Message -----
From:
To:
Sent: Sunday, June 02, 2002 2:57 AM
Subject: Re: How to See the Witness Cones


> I have always had a problem seeing the cones in both my small and large
> electric kiln. Then I remembered something I had heard at a workshop years
> ago. So long ago that I do not remember where it came from. I now put a
> thin line of red iron oxide on each edge of the cones and have absolutely
no
> trouble seeing the cones, even without a safety glass.
>
> Hope that this idea might help.
>
> Chris Taylor
>
>
____________________________________________________________________________
__
> 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.
>

Ned Ludd on mon 3 jun 02


>Please!!!!!!!
>Do not put Red Iron Oxide or anything else on the edge or surface of the
>cones. This will affect the deformation of the cone and give you
unreliable
>results on the equivalent temperature of the cone. Use a brick with RIO
>lines on it behind the cones to help see them.
>
>Best regards,
>
>Tim Frederich

I realise that Tim's advice bears upon cone visibility at temperature
in electric kilns, but anyone trying to use this striped brick method
in a flame fired kiln at cone nine and up will be likely be very
frustrated. I know I was, even with welder's goggles.

Thought I'd pass this on: In my recent firing I enjoyed my best view
at cone ten and eleven. This is what I did differently. While loading
the ware I kept a narrow channel empty, like a lane, front to back on
the top shelf in the 18 cu ft kiln. Top shelf, and the one behind it,
only because it's the level where I place my cones. Near, but not
at, the front of the empty lane I put the cone pack, situated about
14 inches from the spy hole in the brick door. Viewed from my spy,
there was nothing directly behind the cones at all, except, a couple
of feet back, the wall. Even when the cones became virtually
invisible around peak temp. I could still see where their bending
shapes were against the still-distinct brick pattern in the back
wall. If you're desperate, try this. You'll see if it's worth a few
pots being left behind for next firing.

best

Ned

Frederich, Tim on mon 3 jun 02


Please!!!!!!!
Do not put Red Iron Oxide or anything else on the edge or surface of the
cones. This will affect the deformation of the cone and give you unreliable
results on the equivalent temperature of the cone. Use a brick with RIO
lines on it behind the cones to help see them.

Best regards,

Tim Frederich

-----Original Message-----
From: CTaylor174@AOL.COM [mailto:CTaylor174@AOL.COM]
Sent: Sunday, June 02, 2002 3:58 AM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Re: How to See the Witness Cones


I have always had a problem seeing the cones in both my small and large
electric kiln. Then I remembered something I had heard at a workshop years
ago. So long ago that I do not remember where it came from. I now put a
thin line of red iron oxide on each edge of the cones and have absolutely no
trouble seeing the cones, even without a safety glass.

Hope that this idea might help.

Chris Taylor

____________________________________________________________________________
__
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.

Steve Mills on mon 3 jun 02


Tommy,

I have never found that cooling the cone momentarily in order to see
them has had any ill effect on a firing, I don't do it all the time,
just occasionally, but no noticeable difference. So why the *serious no-
no*?

I like the magnification theory!

Steve
Bath
UK

In message , Tommy Humphries writes
> This is the absolute best way to actually see the cones, witho=
>ut
>introducing air, or whatever to cool the conepack a bit, which is a serio=
>us
>no-no.
>
>Now for a question...when you open a peephole in an electric kiln, cold a=
>ir
>will enter the kiln, especially if there is a vent going...this cold air
>forms a "bubble" around the peephole. Is it my imagination or is there a
>slight magnification of objects away from the peephole, due to the denser
>cold air? It always seems that I can see the most minute details of the
>bricks and elements opposite the peeps...could be another reason to posit=
>ion
>the cones away from the peeps...magnification!
>
>Tommy
>
>
>----- Original Message -----
>From:
>To:
>Sent: Sunday, June 02, 2002 2:57 AM
>Subject: Re: How to See the Witness Cones
>
>
>> I have always had a problem seeing the cones in both my small and large
>> electric kiln. Then I remembered something I had heard at a workshop ye=
>ars
>> ago. So long ago that I do not remember where it came from. I now put=
> a
>> thin line of red iron oxide on each edge of the cones and have absolute=
>ly
>no
>> trouble seeing the cones, even without a safety glass.
>>
>> Hope that this idea might help.
>>
>> Chris Taylor
>>
>>
>_________________________________________________________________________=
>___
>__
>> 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.
>>

--
Steve Mills
Bath
UK

Steve Mills on mon 3 jun 02


This has been said before, but it still works: a short blast from a hair
drier (on hot if you like, it's still cooler than in the kiln) through
the spy hole, and bingo!

Steve
Bath
UK


In message , Bacia Edelman writes
>Some years ago, I phoned a troubleshooter at Orton Cone Co.
>and he told me that the iron oxide affected the melt of the
>cones. I therefore abided by his advice and now have
>some trouble again seeing the cones in elec. kilns unless there
>is a clear sight line to the rear of kiln and one can see
>the elements beyond the cone pack. That is not always possible to
>achieve.
>Bacia
>
>At 03:57 AM 06/02/2002 EDT, you wrote:
>>I have always had a problem seeing the cones in both my small and large
>>electric kiln. Then I remembered something I had heard at a workshop yea=
>rs
>>ago. So long ago that I do not remember where it came from. I now put =
>a
>>thin line of red iron oxide on each edge of the cones and have absolutel=
>y no
>>trouble seeing the cones, even without a safety glass.
>>
>>Hope that this idea might help.
>>
>>Chris Taylor
>>
>>________________________________________________________________________=
>___
>___
>>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.
>>
>
>
>
>Bacia Edelman Madison, Wisconsin
>http://users.skynet.be/russel.fouts/bacia.htm
>http://www.silverhawk5.com/edelman/index.html

--
Steve Mills
Bath
UK

Bacia Edelman on mon 3 jun 02


Say, Steve:
Good advice. I have two old hair dryers in studio and will
use one if necessary. I don't remember seeing this advice on Clayart
before. Thanks.
At least Tim Frederich of Orton Co. corroborates what I wrote
yest. about not painting iron oxide on the edges of cones.

Are you dancing on the streets and painting your face as I
just saw on BBC America in honor of Queen Elizabeth?
Cheerio! Bacia

At 10:21 AM 06/03/2002 +0100, you wrote:
>This has been said before, but it still works: a short blast from a hair
>drier (on hot if you like, it's still cooler than in the kiln) through
>the spy hole, and bingo!
>
>Steve
>Bath
>UK
>
>
>In message , Bacia Edelman writes
>>Some years ago, I phoned a troubleshooter at Orton Cone Co.
>>and he told me that the iron oxide affected the melt of the
>>cones. I therefore abided by his advice and now have
>>some trouble again seeing the cones in elec. kilns unless there
>>is a clear sight line to the rear of kiln and one can see
>>the elements beyond the cone pack. That is not always possible to
>>achieve.
>>Bacia
>>
>>At 03:57 AM 06/02/2002 EDT, you wrote:
>>>I have always had a problem seeing the cones in both my small and large
>>>electric kiln. Then I remembered something I had heard at a workshop yea=
>>rs
>>>ago. So long ago that I do not remember where it came from. I now put =
>>a
>>>thin line of red iron oxide on each edge of the cones and have absolutel=
>>y no
>>>trouble seeing the cones, even without a safety glass.
>>>
>>>Hope that this idea might help.
>>>
>>>Chris Taylor
>>>
>>>________________________________________________________________________=
>>___
>>___
>>>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.
>>>
>>
>>
>>
>>Bacia Edelman Madison, Wisconsin
>>http://users.skynet.be/russel.fouts/bacia.htm
>>http://www.silverhawk5.com/edelman/index.html
>
>--
>Steve Mills
>Bath
>UK
>
>___________________________________________________________________________
___
>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.
>



Bacia Edelman Madison, Wisconsin
http://users.skynet.be/russel.fouts/bacia.htm
http://www.silverhawk5.com/edelman/index.html

Tommy Humphries on mon 3 jun 02


Well, for the record, neither have I, but Tim Frederich from Orton advises
against it because it can "Freeze" the surface of the cones causing them to
not bend soon enough.

Tommy

--- Original Message -----
From: "Steve Mills"


> Tommy,
>
> I have never found that cooling the cone momentarily in order to see
> them has had any ill effect on a firing, I don't do it all the time,
> just occasionally, but no noticeable difference. So why the *serious no-
> no*?
>
> I like the magnification theory!
>
> Steve
> Bath
> UK
>
> In message , Tommy Humphries writes
> > This is the absolute best way to actually see the cones, witho=
> >ut
> >introducing air, or whatever to cool the conepack a bit, which is a
serio=
> >us
> >no-no.
> >
> >Now for a question...when you open a peephole in an electric kiln, cold
a=
> >ir
> >will enter the kiln, especially if there is a vent going...this cold air
> >forms a "bubble" around the peephole. Is it my imagination or is there a
> >slight magnification of objects away from the peephole, due to the denser
> >cold air? It always seems that I can see the most minute details of the
> >bricks and elements opposite the peeps...could be another reason to
posit=
> >ion
> >the cones away from the peeps...magnification!
> >
> >Tommy
> >
> >

Frederich, Tim on mon 3 jun 02


Please!!!!!!!!

Do not blow air into the peepholes to try to see the cones. This can cause
the cone to "freeze" and stay in position. You may find the next cone
moving long before the cone that was beginning to deform will move again.
You will also take the chance of blowing dirt in on the partially melted
glaze surface of your pots. Please use a good pair of colored safety
glasses and allow the kiln to "breathe" for a few seconds after pulling the
peephole plug. Then look into the kiln. You should be able to see the cones
without a problem.

Best regards,

Tim Frederich

-----Original Message-----
From: Steve Mills [mailto:stevemills@MUDSLINGER.DEMON.CO.UK]
Sent: Monday, June 03, 2002 5:21 AM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Re: How to See the Witness Cones


This has been said before, but it still works: a short blast from a hair
drier (on hot if you like, it's still cooler than in the kiln) through
the spy hole, and bingo!

Steve
Bath
UK


In message , Bacia Edelman writes
>Some years ago, I phoned a troubleshooter at Orton Cone Co.
>and he told me that the iron oxide affected the melt of the
>cones. I therefore abided by his advice and now have
>some trouble again seeing the cones in elec. kilns unless there
>is a clear sight line to the rear of kiln and one can see
>the elements beyond the cone pack. That is not always possible to
>achieve.
>Bacia
>
>At 03:57 AM 06/02/2002 EDT, you wrote:
>>I have always had a problem seeing the cones in both my small and large
>>electric kiln. Then I remembered something I had heard at a workshop yea=
>rs
>>ago. So long ago that I do not remember where it came from. I now put =
>a
>>thin line of red iron oxide on each edge of the cones and have absolutel=
>y no
>>trouble seeing the cones, even without a safety glass.
>>
>>Hope that this idea might help.
>>
>>Chris Taylor
>>
>>________________________________________________________________________=
>___
>___
>>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.
>>
>
>
>
>Bacia Edelman Madison, Wisconsin
>http://users.skynet.be/russel.fouts/bacia.htm
>http://www.silverhawk5.com/edelman/index.html

--
Steve Mills
Bath
UK

____________________________________________________________________________
__
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.

Steve Mills on mon 3 jun 02


I see, however I think you'd have to subject it to a prolonged blast of
cold air to do that.

Thanks

Steve


In message <007901c20b04$bbe1b020$7405fea9@thump>, Tommy Humphries
writes
>Well, for the record, neither have I, but Tim Frederich from Orton advises
>against it because it can "Freeze" the surface of the cones causing them to
>not bend soon enough.
>
>Tommy
>
>--- Original Message -----
>From: "Steve Mills"
>
>
>> Tommy,
>>
>> I have never found that cooling the cone momentarily in order to see
>> them has had any ill effect on a firing, I don't do it all the time,
>> just occasionally, but no noticeable difference. So why the *serious no-
>> no*?
>>
>> I like the magnification theory!
>>
>> Steve
>> Bath
>> UK
>>
>> In message , Tommy Humphries writes
>> > This is the absolute best way to actually see the cones, witho=
>> >ut
>> >introducing air, or whatever to cool the conepack a bit, which is a
>serio=
>> >us
>> >no-no.
>> >
>> >Now for a question...when you open a peephole in an electric kiln, cold
>a=
>> >ir
>> >will enter the kiln, especially if there is a vent going...this cold air
>> >forms a "bubble" around the peephole. Is it my imagination or is there
a
>> >slight magnification of objects away from the peephole, due to the
denser
>> >cold air? It always seems that I can see the most minute details of the
>> >bricks and elements opposite the peeps...could be another reason to
>posit=
>> >ion
>> >the cones away from the peeps...magnification!
>> >
>> >Tommy
>> >
>> >
>
>

--
Steve Mills
Bath
UK

Mert & Holly Kilpatrick on tue 4 jun 02


bruec@anv.net wrote:


>Personally, if the red iron on the cone works visually, then I would
experiment. Place two cone packs side >by side in the kiln, one with the
iron treatment and one without. See for yourself how much if any the cones
>vary. If they are slightly off, but consistent, it will still work.

We just tried that on two ^6 cones in an electric kiln, and we couldn't see
any difference in the bending of the cones, with a line of iron oxide on one
of them. However, we couldn't see that cone any better through the peephole
either.

Holly

CTaylor174@AOL.COM on tue 4 jun 02


Tim:
Personally, I have been firing crystalline glazes which are "iffy" at the
best of times. I have had a very close look at the temp which cones 8,9 and
10 have fallen and so far in about ten firings it has been almost the exact
temperature. Naturally, it depends on whether the kiln is loaded fully or
not.

I do however think that your idea about putting red iron oxide on a brick
behind the cones is a good idea and I will certainly try it.

Regards Christine Taylor

Gail Dapogny on tue 4 jun 02


I ran this stripe idea by others in our potters' guild so we tried it in
our gas kiln. At cone 9 (or thearabouts), we could see nothing!!! I fired
it blind (color, smell, time) to the end.

Possibly it works in a small kiln, but not in this one (90 cub ft.) We
just try to leave blank kiln wall behind the cones.With goggles, it works
okay.
---Gail


> Use a brick with RIO
>>lines on it behind the cones to help see the cones.
>>
>>Best regards,
>>
>>Tim Frederich

Gail Dapogny
1154 Olden Road
Ann Arbor, MI 48103-3005
(734) 665-9816
gdapogny@umich.edu
http://www.silverhawk.com/ex99/dapogny (single historical photo - no longer
registered with Silverhawk)

bruec@anv.net on tue 4 jun 02


Personally, if the red iron on the cone works visually, then I would
experiment. Place two cone packs side by side in th=
e kiln, one with the iron treatment and one without. See for yourself how
much if any the cones vary. If they are slightl=
y off, but consistent, it will still work.

Before cones, people used things like draw rings to check the maturation of
the firing. How accurate was that?

I can understand Orton taking their position, I would look at it like a
disclaimer.

Original Message:
-----------------
From: Ned Ludd nludd@SHOCKING.COM
Date: Mon, 3 Jun 2002 21:27:45 -0700
To: CLAYART@LSV.CERAMICS.ORG
Subject: Re: How to See the Witness Cones


>Please!!!!!!!
>Do not put Red Iron Oxide or anything else on the edge or surface of the
>cones. This will affect the deformation of the cone and give you
unreliable
>results on the equivalent temperature of the cone. Use a brick with RIO
>lines on it behind the cones to help see them.
>
>Best regards,
>
>Tim Frederich



--------------------------------------------------------------------
mail2web - Check your email from the web at
http://mail2web.com/ .

Steve Mills on tue 4 jun 02


In message , Bacia Edelman writes
>Say, Steve:
>Good advice. I have two old hair dryers in studio and will
>use one if necessary. I don't remember seeing this advice on Clayart
>before. Thanks.
>At least Tim Frederich of Orton Co. corroborates what I wrote
>yest. about not painting iron oxide on the edges of cones.
>
>Are you dancing on the streets and painting your face as I
>just saw on BBC America in honor of Queen Elizabeth?
>Cheerio! Bacia
>
We dance on the streets as a matter of course, don't need a Jubilee as
an excuse, But then I've been involved in Morris Dancing for a good few
years now, all in the cause of Music, exercise, and consuming lots of
good strong Ale!
--
Steve Mills
Bath
UK

Brian Crocker on wed 5 jun 02


G'Day All,

I was told many years ago that cones are an indicating device and should be
used accompanied with a pyrometer and then the results recorded so that they
can be used at some time later.

If the cones are marked with iron oxide and the details recorded, then the
results surely must be the same when used in the same way at a later date ?
? ?

Kind regards,

CROC.
===========================
----- Original Message -----
From: "Mert & Holly Kilpatrick"
To:
Sent: Wednesday, June 05, 2002 10:20 AM
Subject: Re: How to See the Witness Cones


> bruec@anv.net wrote:
>
>
> >Personally, if the red iron on the cone works visually, then I would
> experiment. Place two cone packs side >by side in the kiln, one with the
> iron treatment and one without. See for yourself how much if any the cones
> >vary. If they are slightly off, but consistent, it will still work.
>
> We just tried that on two ^6 cones in an electric kiln, and we couldn't
see
> any difference in the bending of the cones, with a line of iron oxide on
one
> of them. However, we couldn't see that cone any better through the
peephole
> either.
>
> Holly
>
>
____________________________________________________________________________
__
> 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.
>

Snail Scott on wed 5 jun 02


At 05:30 PM 6/5/02 +0930, you wrote:

>If the cones are marked with iron oxide and the details recorded, then the
>results surely must be the same when used in the same way at a later date ?


Since the fluxing action of iron is affected by
the atmosphere of the kiln, you'd have to be
sure that the reduction levels were identical
as well, to ensure consistent readings. Also
you'd need a consistent way to apply the iron
to each cone identically.

-Snail