Sandi Nelson on tue 7 nov 06
Okay...glazed all day yesterday and have my little Liberty Belle loaded. I am changing the program to the one in Mastering ^6 Glazes book...my questions:
in the Liberty Belle book, my ^6 final temp is 2232...is is correct that I would lower that temp by 30 degrees (2202) because I am soaking at the final temp? (I've never soaked at the high end before...am I correct that I reduce the final temp by 20 degrees for every 10 minutes of soak time?) That will lower my next to final to 1952...the books states that the last ramp rate must be @ 108/hr. and there will always be 250 degrees between the next to final and final temp. OR...do I go stricktly by what is in the book and follow the 2190 final temp?
(I know, I'm green, but this forum is so helpful...THANK YOU!)
Sandi
Mark Tigges on tue 7 nov 06
On Tue, Nov 07, 2006 at 09:36:54AM -0500, Sandi Nelson wrote:
> Okay...glazed all day yesterday and have my little Liberty Belle
> loaded. I am changing the program to the one in Mastering ^6 Glazes
> book...my questions: in the Liberty Belle book, my ^6 final temp is
> 2232...is is correct that I would lower that temp by 30 degrees
> (2202) because I am soaking at the final temp? (I've never soaked
> at the high end before...am I correct that I reduce the final temp
> by 20 degrees for every 10 minutes of soak time?) That will lower my
> next to final to 1952...the books states that the last ramp rate
> must be @ 108/hr. and there will always be 250 degrees between the
> next to final and final temp. OR...do I go stricktly by what is in
> the book and follow the 2190 final temp? (I know, I'm green, but
> this forum is so helpful...THANK YOU!) Sandi
My kiln is not controlled by silicon, rather carbon. Me.
This means that I turn the dials myself to effect the appropriate rate
of change of temperature. I know when to do it since I wrote a
program that runs on a laptop I have in the garage that helps me graph
the progress of the firing.
So, that said, I am always finishing the top end of the firing based
on the progress of witness cones. It is certainly true that all of
the firings are very close to each other, but sometimes I start my
soak at 1190 (1200 is the apex of the R&H schedule), sometimes at
1200. It depends on the state of the cones when that temperature is
reached. I attribute the variability to things like tightness of
pack, efficiency of the vent to draw through the kiln, things like
this which change every firing.
So, don't sweat the small stuff. I try NEVER to go over 1200. The
reason is that my clay body (laguna bmix5) exhibits blistering if you
reach cone 7. (That blistering is not uncommon, I have used another
body similar to bmix that blistered much worse, even at cone 6.)
What it comes down to is I begin the soak right around when cone 5.5
is reached this is usually below 1200, a 15-20 minute soak brings cone
6 down. Often the kiln will continue to creep up to 1200. So, my
advice is to put witness cones in the kiln, learn the kiln for a few
firings, and you'll know better how to adjust the schedule to fit you.
I would err on the side of caution and start the soak earlier rather
than risk too much heatwork applied to your body. But ultimately,
these small difference will likely never manifest themselves in
visible differences.
NB. It is my personal opinion that one shouldn't rely on the computer
anyways. I advise being there.
Mark.
--
http://www.m2crafts.ca
m2crafts [at] gmail
John Hesselberth on tue 7 nov 06
On Nov 7, 2006, at 9:36 AM, Sandi Nelson wrote:
> Okay...glazed all day yesterday and have my little Liberty Belle
> loaded. I am changing the program to the one in Mastering ^6
> Glazes book...my questions:
> in the Liberty Belle book, my ^6 final temp is 2232...is is correct
> that I would lower that temp by 30 degrees (2202) because I am
> soaking at the final temp? (I've never soaked at the high end
> before...am I correct that I reduce the final temp by 20 degrees
> for every 10 minutes of soak time?) That will lower my next to
> final to 1952...the books states that the last ramp rate must be @
> 108/hr. and there will always be 250 degrees between the next to
> final and final temp. OR...do I go stricktly by what is in the
> book and follow the 2190 final temp?
> (I know, I'm green, but this forum is so helpful...THANK YOU!)
> Sandi
>
Hi Sandi,
As we note in the book that final temperature has to be adjusted to
marry it to your kiln and your thermocouples. I have found for a
number a kilns I have worked with that somewhere between 2185 and
2200 usually works. But that is why you use cones on every shelf and
in every firing. Learn to see them and let them be your guide. They
are the "gold standard", thermocouples are not. They are usually off
in their calibration at these high temperatures and they do drift
with age.
Good luck on your firing,
John
Ron Roy on wed 8 nov 06
Hi Mark,
I agree - be there at the end.
I start to soak when cone 6 starts to move - like to 1 oclock - I use a
controller and when the cone is far enough down I skip step to the next
ramp.
Essentially what you are doing without the controller.
Usually takes about 20 min - you will get used to it - and it does depend
on how your electricity fuxtuates (time of day) and how tightly packed the
kiln is.
How fast you are firing during the last 100C has an effect as well - if you
slow up you will not have to soak as long to get to the end.
RR
>On Tue, Nov 07, 2006 at 09:36:54AM -0500, Sandi Nelson wrote:
>> Okay...glazed all day yesterday and have my little Liberty Belle
>> loaded. I am changing the program to the one in Mastering ^6 Glazes
>> book...my questions: in the Liberty Belle book, my ^6 final temp is
>> 2232...is is correct that I would lower that temp by 30 degrees
>> (2202) because I am soaking at the final temp? (I've never soaked
>> at the high end before...am I correct that I reduce the final temp
>> by 20 degrees for every 10 minutes of soak time?) That will lower my
>> next to final to 1952...the books states that the last ramp rate
>> must be @ 108/hr. and there will always be 250 degrees between the
>> next to final and final temp. OR...do I go stricktly by what is in
>> the book and follow the 2190 final temp? (I know, I'm green, but
>> this forum is so helpful...THANK YOU!) Sandi
>
>My kiln is not controlled by silicon, rather carbon. Me.
>
>This means that I turn the dials myself to effect the appropriate rate
>of change of temperature. I know when to do it since I wrote a
>program that runs on a laptop I have in the garage that helps me graph
>the progress of the firing.
>
>So, that said, I am always finishing the top end of the firing based
>on the progress of witness cones. It is certainly true that all of
>the firings are very close to each other, but sometimes I start my
>soak at 1190 (1200 is the apex of the R&H schedule), sometimes at
>1200. It depends on the state of the cones when that temperature is
>reached. I attribute the variability to things like tightness of
>pack, efficiency of the vent to draw through the kiln, things like
>this which change every firing.
>
>So, don't sweat the small stuff. I try NEVER to go over 1200. The
>reason is that my clay body (laguna bmix5) exhibits blistering if you
>reach cone 7. (That blistering is not uncommon, I have used another
>body similar to bmix that blistered much worse, even at cone 6.)
>
>What it comes down to is I begin the soak right around when cone 5.5
>is reached this is usually below 1200, a 15-20 minute soak brings cone
>6 down. Often the kiln will continue to creep up to 1200. So, my
>advice is to put witness cones in the kiln, learn the kiln for a few
>firings, and you'll know better how to adjust the schedule to fit you.
>I would err on the side of caution and start the soak earlier rather
>than risk too much heatwork applied to your body. But ultimately,
>these small difference will likely never manifest themselves in
>visible differences.
>
>NB. It is my personal opinion that one shouldn't rely on the computer
>anyways. I advise being there.
>
>Mark.
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Eleanora Eden on fri 10 nov 06
Hi Ron,
Just for clarification on this critical point. What I think you are saying is that whatever
your pyrometer reads when your goal cone starts to move, that becomes your
end point. You soak there for 15 minutes, or until the cone is over, before proceeding
to next ramp on the schedule outlined in your book.
This is also assuming that one is adjusting controls so that this process starts at the
same time at the top and bottom of the kiln.
Do I have that correctly? And this would pertain as well, I expect, to my ^1-3 range firings.
Thanks as always.
Eleanora
>Hi Mark,
>
>I agree - be there at the end.
>
>I start to soak when cone 6 starts to move - like to 1 oclock - I use a
>controller and when the cone is far enough down I skip step to the next
>ramp.
>
>Essentially what you are doing without the controller.
>
>Usually takes about 20 min - you will get used to it - and it does depend
>on how your electricity fuxtuates (time of day) and how tightly packed the
>kiln is.
>
>How fast you are firing during the last 100C has an effect as well - if you
>slow up you will not have to soak as long to get to the end.
>
>RR
>
>>On Tue, Nov 07, 2006 at 09:36:54AM -0500, Sandi Nelson wrote:
>>> Okay...glazed all day yesterday and have my little Liberty Belle
>>> loaded. I am changing the program to the one in Mastering ^6 Glazes
>>> book...my questions: in the Liberty Belle book, my ^6 final temp is
>>> 2232...is is correct that I would lower that temp by 30 degrees
>>> (2202) because I am soaking at the final temp? (I've never soaked
>>> at the high end before...am I correct that I reduce the final temp
>>> by 20 degrees for every 10 minutes of soak time?) That will lower my
>>> next to final to 1952...the books states that the last ramp rate
>>> must be @ 108/hr. and there will always be 250 degrees between the
>>> next to final and final temp. OR...do I go stricktly by what is in
>>> the book and follow the 2190 final temp? (I know, I'm green, but
>>> this forum is so helpful...THANK YOU!) Sandi
>>
>>My kiln is not controlled by silicon, rather carbon. Me.
>>
>>This means that I turn the dials myself to effect the appropriate rate
>>of change of temperature. I know when to do it since I wrote a
>>program that runs on a laptop I have in the garage that helps me graph
>>the progress of the firing.
>>
>>So, that said, I am always finishing the top end of the firing based
>>on the progress of witness cones. It is certainly true that all of
>>the firings are very close to each other, but sometimes I start my
>>soak at 1190 (1200 is the apex of the R&H schedule), sometimes at
>>1200. It depends on the state of the cones when that temperature is
>>reached. I attribute the variability to things like tightness of
>>pack, efficiency of the vent to draw through the kiln, things like
>>this which change every firing.
>>
>>So, don't sweat the small stuff. I try NEVER to go over 1200. The
>>reason is that my clay body (laguna bmix5) exhibits blistering if you
>>reach cone 7. (That blistering is not uncommon, I have used another
>>body similar to bmix that blistered much worse, even at cone 6.)
>>
>>What it comes down to is I begin the soak right around when cone 5.5
>>is reached this is usually below 1200, a 15-20 minute soak brings cone
>>6 down. Often the kiln will continue to creep up to 1200. So, my
>>advice is to put witness cones in the kiln, learn the kiln for a few
>>firings, and you'll know better how to adjust the schedule to fit you.
>>I would err on the side of caution and start the soak earlier rather
>>than risk too much heatwork applied to your body. But ultimately,
>>these small difference will likely never manifest themselves in
>>visible differences.
>>
>>NB. It is my personal opinion that one shouldn't rely on the computer
>>anyways. I advise being there.
>>
>>Mark.
>
>Ron Roy
>RR#4
>15084 Little Lake Road
>Brighton, Ontario
>Canada
>K0K 1H0
>
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Ron Roy on sun 12 nov 06
Hi Eleanora,
Yes - what ever cone you are firing to.
You are trying to find out when (what cone bend) to have so that when you
start your soak you will arrive at your final cone bend.
Like cone 6 just starting (1 oclock) - start soak - in 20 min. cone 6 is at
5 oclock - start cooling down.
If you wanted to have cone 6 at 2 oclock after the soak you might have to
start your soak at cone 5 at 4 oclock.
All depends on how fast (or slow) your kiln is firing - you get there by
making careful notes - it becomes automatic after a number of tries.
You have to keep an eye on things of course as elements change and loads
vary - but you can adjust the soak time - the longer it is the more
flexibility you have.
RR
>Just for clarification on this critical point. What I think you are
>saying is that whatever
>your pyrometer reads when your goal cone starts to move, that becomes your
>end point. You soak there for 15 minutes, or until the cone is over,
>before proceeding
>to next ramp on the schedule outlined in your book.
>
>This is also assuming that one is adjusting controls so that this process
>starts at the
>same time at the top and bottom of the kiln.
>
>Do I have that correctly? And this would pertain as well, I expect, to my
>^1-3 range firings.
>
>Thanks as always.
>
>Eleanora
>
>
>
>>Hi Mark,
>>
>>I agree - be there at the end.
>>
>>I start to soak when cone 6 starts to move - like to 1 oclock - I use a
>>controller and when the cone is far enough down I skip step to the next
>>ramp.
>>
>>Essentially what you are doing without the controller.
>>
>>Usually takes about 20 min - you will get used to it - and it does depend
>>on how your electricity fuxtuates (time of day) and how tightly packed the
>>kiln is.
>>
>>How fast you are firing during the last 100C has an effect as well - if you
>>slow up you will not have to soak as long to get to the end.
>>
>>RR
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
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