Eleanora Eden on sat 25 nov 06
Ron and John, and all,
Want to report that this made a whole big difference in my most recent firing. I had gone
successfully to cone 1 exactly and now wanted to go exactly to cone 3, comparing clay
and glaze at both temperatures.
It went without a hitch. As soon as cone 1 started to move I adjusted my computer to
soak at that point for 15 m then start cool down. On both peep and witness shelf cones, ^ 3 was
arching down like in that little video clip, and ^ 4 soldierly upright.
Clay and glaze were both fabulous at ^3 so now I am officially going there.
Thanks as always,
Eleanora
>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
>>
>>______________________________________________________________________________
>>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.
>
>
>--
>Bellows Falls Vermont
>www.eleanoraeden.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.
--
Bellows Falls Vermont
www.eleanoraeden.com
Ron Roy on sun 26 nov 06
Hi Eleanora,
When you wrote "As soon as cone 1 started to move I adjusted my computer
to" I think you ment cone 3 started to move right?
Otherwise you would have had to wait for hours for cone 3 to fall.
RR
>Ron and John, and all,
>
>Want to report that this made a whole big difference in my most recent
>firing. I had gone
>successfully to cone 1 exactly and now wanted to go exactly to cone 3,
>comparing clay
>and glaze at both temperatures.
>
>It went without a hitch. As soon as cone 1 started to move I adjusted my
>computer to
>soak at that point for 15 m then start cool down. On both peep and
>witness shelf cones, ^ 3 was
>arching down like in that little video clip, and ^ 4 soldierly upright.
>
>Clay and glaze were both fabulous at ^3 so now I am officially going there.
>
>Thanks as always,
>
>Eleanora
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
| |
|
