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Seeing witness cones


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#1 Stuart

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Posted 08 January 2012 - 07:21 AM

Hi,

My first post on this forum!

Do others have problems seeing cones through the peephole of a kiln when the kiln is at 1200degC / 2100degF? The problem I have is that the inside of the kiln provides very little contrast to see the cones. At that temperature it is so bright inside that if there isn't sufficient contrast between the cones and the kiln interior they are simply invisible.

Has anyone else had this problem? My guess is to make a small slab of clay and coat it in dark underglaze to put behind the cones, but I'm not sure if that will work.

Thank you,

Stuart.

#2 meisie

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Posted 08 January 2012 - 07:56 AM

Hi,

My first post on this forum!

Do others have problems seeing cones through the peephole of a kiln when the kiln is at 1200degC / 2100degF? The problem I have is that the inside of the kiln provides very little contrast to see the cones. At that temperature it is so bright inside that if there isn't sufficient contrast between the cones and the kiln interior they are simply invisible.

Has anyone else had this problem? My guess is to make a small slab of clay and coat it in dark underglaze to put behind the cones, but I'm not sure if that will work.

Thank you,

Stuart.


I can't see them to save my life. I tried welding goggles to no avail. I think it's my age and my eyesight. I look in and all I see is a red glow and maybe a shadow which I assume is an edge of something. I keep looking but it's always the same. Sorry.

#3 Natas Setiabudhi

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Posted 08 January 2012 - 08:07 AM

Hi stuart
Ya it's common problem for the potters. Usually if the atmosphere not reduction the cone will be seen clear enough. I have simple way to solve that problem, just blow it. So you just closer the peephole and blow it for several times. But remember don't too close, your mouth will burnt. I will guarantee it will be succeed.
I usually put the small test piece glazed beside the cone to make sure glaze melted well. The piece have a small hole so you can draw it by iron. You will see directly the glazes are melted well.
Okay good luck!

Natas Setiabudhi
Kupu Ceramic Studio, Indonesia
www.butterflyceramic.blogspot.com

#4 Matt Oz

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Posted 08 January 2012 - 09:24 AM

Here is a helpful link that goes to the Paragon kiln website, written by Arnold Howard.

How do you position the cones on the shelf so that you can see them through a peephole?

#5 Pres

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Posted 08 January 2012 - 10:03 AM

Here is a helpful link that goes to the Paragon kiln website, written by Arnold Howard.

How do you position the cones on the shelf so that you can see them through a peephole?


I guess I do everything-breaking the rules. 1)I set up my cone back so that it sets parallel to the peep hole, perpendicular to the wall. 2) the cones are set at opposite angles along the length of the coil of clay. 3) I set the cone very close to the peep hole so that I can see each cone when loading the kiln. 4) I pack a kiln way to tight to see an element on the other side of the kiln.

Simply retired teacher, not dead, living the dream. on and on and. . . . on. . . .                                                                                 http://picworkspottery.blogspot.com/


#6 Matt Oz

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Posted 08 January 2012 - 10:41 AM


Here is a helpful link that goes to the Paragon kiln website, written by Arnold Howard.

How do you position the cones on the shelf so that you can see them through a peephole?


I guess I do everything-breaking the rules. 1)I set up my cone back so that it sets parallel to the peep hole, perpendicular to the wall. 2) the cones are set at opposite angles along the length of the coil of clay. 3) I set the cone very close to the peep hole so that I can see each cone when loading the kiln. 4) I pack a kiln way to tight to see an element on the other side of the kiln.


Thank you for the alternative info, important points.

#7 OffCenter

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Posted 08 January 2012 - 12:37 PM

As someone above has mentioned, blowing into the kiln helps. The hints from Paragon are helpful about distance and loading so that the cones stand out against elements in the background would probably work but who wants to waste that much space in a regular firing?

Jim
E pur si muove.

"But it does move," said Galileo under his breath.

#8 Stuart

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Posted 08 January 2012 - 03:43 PM

Some excellent suggestions there guys - thank you very much for your replies!!

#9 Benhim

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Posted 08 January 2012 - 10:55 PM

Get yourself a pair of welder's glasses if you don't already have some. They really helped me to see better in the kiln with out damaging my eyes while I was in college doing high fire ceramics. Staggering cones, placement and cleaning out the kiln can make it easier to see. A heat gun can inject clean air that's hot but cool compared to the kiln temperature. Quickly blasting the port with a heat gun can clear the air around the cones and very slightly cool them making them more visible.

BenCo Ceramics


#10 Rakuken

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Posted 09 January 2012 - 02:26 PM

I use a light-emitting diode (LED) flash light to look at the cones. I can see my cones at cone 10 in reduction. It works!!

#11 Arnold Howard

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Posted 09 January 2012 - 05:28 PM

The hints from Paragon are helpful about distance and loading so that the cones stand out against elements in the background would probably work but who wants to waste that much space in a regular firing?


As an alternative, raise the cones off the shelf so you can see them through the peephole between tall pieces of ware. Support the cones with a post and small piece of kiln shelf.

Sincerely,

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

#12 Arnold Howard

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Posted 09 January 2012 - 05:31 PM

I use a light-emitting diode (LED) flash light to look at the cones. I can see my cones at cone 10 in reduction. It works!!


I've tried that with an electric kiln without success. Has anyone else tried this?

Sincerely,

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

#13 Rakuken

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Posted 09 January 2012 - 06:33 PM


I use a light-emitting diode (LED) flash light to look at the cones. I can see my cones at cone 10 in reduction. It works!!


I've tried that with an electric kiln without success. Has anyone else tried this?

Sincerely,

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


Here is a picture of the flash light I use. Bought it from Costco, the brand name is TechLite. My cones are placed about 3-4 inches inside of the peep hole. I can even see the cone number that's impressed on it while I'm firing. I also use it to look in the raku kiln while firing.


Aloha

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#14 nairda

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Posted 09 January 2012 - 07:26 PM

I dip about 1/4" of the tip of the witness cone in some dark brown slip or underglaze prior to putting it in the kiln. It stands out really well during the firing.

Hi,

My first post on this forum!

Do others have problems seeing cones through the peephole of a kiln when the kiln is at 1200degC / 2100degF? The problem I have is that the inside of the kiln provides very little contrast to see the cones. At that temperature it is so bright inside that if there isn't sufficient contrast between the cones and the kiln interior they are simply invisible.

Has anyone else had this problem? My guess is to make a small slab of clay and coat it in dark underglaze to put behind the cones, but I'm not sure if that will work.

Thank you,

Stuart.



#15 Benhim

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Posted 09 January 2012 - 11:57 PM

Wouldn't that change the chemistry of the cone?

BenCo Ceramics


#16 johnc

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Posted 07 February 2013 - 03:41 AM

Hi so my solution was i came up with a deivice when i fire at cone 9. It drops a weight at cone 9 and a buzzer goes off. Really simple and easy to make. If anyone is intersted to know how to build one or i can build one for you.

#17 JBaymore

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Posted 07 February 2013 - 10:03 AM

Wouldn't that change the chemistry of the cone?


Yes, ot would. Ditto for the suggestions you sometimes see for painting stripes on them and such.

Blowing on the cones has the danger of causing something called "freezing" of the cones. Orton discusses this phenomona. Can cause the cones to misread. Plus unless you dust out your spy ports... you are in danger of blowing dust into the kiln and onto the glazes near (and below) the ports.

There are simple solutions.... arc welding face shield glass filters work wonders. The best thing I have is a gold-plated surface face shield that I use for stoking the main firemouth on the noborigama........ you can see in at even cone 14 clear as day. Expensive though.

best,

.....................john
John Baymore
Immediate Past President; Potters Council
Professor of Ceramics; New Hampshire Insitute of Art

http://www.JohnBaymore.com

#18 justanassembler

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Posted 07 February 2013 - 01:56 PM


Wouldn't that change the chemistry of the cone?


Yes, ot would. Ditto for the suggestions you sometimes see for painting stripes on them and such.

Blowing on the cones has the danger of causing something called "freezing" of the cones. Orton discusses this phenomona. Can cause the cones to misread. Plus unless you dust out your spy ports... you are in danger of blowing dust into the kiln and onto the glazes near (and below) the ports.

There are simple solutions.... arc welding face shield glass filters work wonders. The best thing I have is a gold-plated surface face shield that I use for stoking the main firemouth on the noborigama........ you can see in at even cone 14 clear as day. Expensive though.

best,

.....................john


Blowing into a kiln you also run the risk of blowing any dust that is sitting in the peep (there is usually some sitting there from the plug grinding the hole...) and landing on your fluxed glazes. John is right on about using welding shields, I actually have a pair of shade 3 welders goggles that work fine for most situations, especially anything ^10 or below. The gold plated face shield is an absolutely luxury when it comes to stoking hot kilns--I used to wear one when i was charging glass furnaces @ 2300= degrees and it made the experience completely comfortable.

#19 Mark C.

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Posted 07 February 2013 - 06:27 PM

You can buy or order the face shield glass only at wielding supply shops.
Every area has one just about.
John what are the details on that glass?
Mark
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#20 JBaymore

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Posted 08 February 2013 - 10:39 AM

You can buy or order the face shield glass only at wielding supply shops.
Every area has one just about.
John what are the details on that glass?
Mark


Mark,

I assume you mean the shield?

Here is the most convenient source for one of these. I got mine years agao direct from the manufacturer.

http://www.wardburne...veclothing.html

The one labeled 24K Gold Coated
Didymium II Faceshield
would be about the same as the one I
have.

For stoking the wood kiln the warning on the page is correct......
these shields cut so much infrared (ther real cuplrit from kilns to the eyes...
not IR) that you feel no heat on your face...... and meanwhile as you snuggle in
close...... your hat or shirt is catching fire. (I wear leathers). ;)src="http://ceramicartsda...ault/wink.gif">


best,

...................john


John Baymore
Immediate Past President; Potters Council
Professor of Ceramics; New Hampshire Insitute of Art

http://www.JohnBaymore.com




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