Tjo62@AOL.COM on wed 3 dec 03
When deadlines mean I must fire through the night, I get the kiln through
body reduction and then go to sleep for about 2 and a half hours. I get up and go
check and sleep for another hour and a half and then check and sleep another
hour and check and then usually stay up until it is finished. It makes for a
miserable night and I often have terrible dreams lol! Last time I did this I
dreamed a stonge wind blew the kiln off it's foundation and slamed it against
my neighbors privacy fence. It exploded into a ball of orange flame and the
trees and everything began to burn! It was just horrible! lol I really try to
fire during the day and I am most happy staying home with my eyes on it. Tonya
in Louisville, KY
John Jensen on wed 3 dec 03
I know and agree that one should be in attendance at all times during a
gas firing. Tempting as it is sometimes to take run a little errand, I
always stay on duty. So far so good. But I am wondering what the
prevailing wisdom about those times when only one pilot light with the
baso valve/thermocouple is burning would be. Would it be considered
acceptable to leave such a kiln unattended? What would the risk be in
that case. Still not something I want to do, but
hypothetically.........
John Jensen, Mudbug Pottery
mudbug@toadhouse.com , http://www.toadhouse.com
Kathi LeSueur on wed 3 dec 03
mudbug@TOAD.NET wrote:
>I know and agree that one should be in attendance at all times during a
>gas firing. Tempting as it is sometimes to take run a little errand, I
>always stay on duty. So far so good. But I am wondering what the
>prevailing wisdom about those times when only one pilot light with the
>baso valve/thermocouple is burning would be. Would it be considered
>acceptable to leave such a kiln unattended? What would the risk be in
>that case. Still not something I want to do, but
>hypothetically.........>>>>>
>
My fear with leaving the gas kiln is not that I will have a kiln
accident, but that I will have a car accident and that there won't be
anyone to shut it off. Even with just warm ups on the kiln could
feasibly become dangerous. My kiln can be shut down with the touch of a
button. A relay switch that the blowers and the solonoid on the gas line
are wired into. If the button is hit everything shuts down and won't
come back on again unless the restart button is pushed. The same for a
power failure. The kiln will shut down. Everyone on my street knows
about the red button and how to shut it down in an emergency. But, even
with this safety feature I'm hesitant to leave it.
Kathi
>
>
>
>
Hank Murrow on wed 3 dec 03
Well;
I know I am going to receive some heat for this, but I often do errands
while I am firing, Have been known to go to a movie while firing, often
go to sleep during extended parts of the firing, and always leave the
kiln during my oxidation soaks during the cooling. I have no safety
equipment on the kiln. I spent many hours measuring the heat from the
firing on my rafters and the roof connections and was confident after a
few firings that all was as safe as humanly possible. I have never had
an incident in 46 years of firing gas kilns. Of course, karma or just
hubris might suggest that I am due. I am not suggesting my route for
anyone else, and know that when I have installed kilns for others I
frequently got a migraine the night of the first firing. That is.....I
am pretty careful and do feel the pressure of someone else's
investment.
Hoping my 46 year run of good fortune continues,
Hank in Eugene
On Dec 3, 2003, at 12:50 PM, John Jensen wrote:
> I know and agree that one should be in attendance at all times during a
> gas firing. Tempting as it is sometimes to take run a little errand, I
> always stay on duty. So far so good. But I am wondering what the
> prevailing wisdom about those times when only one pilot light with the
> baso valve/thermocouple is burning would be. Would it be considered
> acceptable to leave such a kiln unattended? What would the risk be in
> that case. Still not something I want to do, but
> hypothetically.........
Gordon Ward on wed 3 dec 03
I too must confess to leaving my gas kiln once red heat is developed.
My kiln is based on Hank's design which you can practically set your
watch by. My first version, which I sold about 12 or 15 years ago, had a
mild steel shell. The mild steel throws off heat like mad and the kiln
room would get quite hot near the end of a firing. The "new" one has a
stainless shell like Hank's. The difference between the two is
dramatic. The stainless hardly throws any heat off, keeping the room
much cooler. This may account for Hank's somewhat relaxed attitude.
Also, about 18 years ago, I fell asleep during a late firing. When I
awoke (with a start) in the early morning, the kiln was firing merrily
along at about cone 16. You can imagine how I felt at the sight. The
stack was a mess and all the pots were completely bloated.
Amazingly, the kiln was fine! While I would never want to repeat this,
and I take extreme precautions not to, the experience has given me
alot of confidence in the design of the kiln.
I still think it's a good idea to stay close and don't go to sleep!
Gordon
Vince Pitelka on wed 3 dec 03
> I know and agree that one should be in attendance at all times during a
> gas firing. Tempting as it is sometimes to take run a little errand, I
> always stay on duty. So far so good. But I am wondering what the
> prevailing wisdom about those times when only one pilot light with the
> baso valve/thermocouple is burning would be. Would it be considered
> acceptable to leave such a kiln unattended? What would the risk be in
> that case. Still not something I want to do, but
> hypothetically.........
John -
I am not sure I understand your concern. Why should one be in attendance at
all times during a gas firing? If you have a good gas kiln wiht a proper
Baso safety system, why wouldn't you be willing to leave it unattended?
Once I get to know a gas kiln, I have never hesitated to leave it unattended
for periods of time if it has a Baso safety system properly installed and
properly working.
I really do not see any risk, and in 35 years of firing gas kilns I have
never had a problem because of leaving a gas kiln unattended. But I do have
an ability to wake up when I need to, even if my alarm clock fails.
I wish that had been true of one of my students eight or nine years ago when
he went home to take a nap in the late morning, just after finishing body
reduction in our newly-built gas downdraft kiln, and failed to wake up until
after midnight. Melted the shelves, furniture, and pots, and did serious
damage to the inside of the kiln. But that wasn't the fault of the Baso
valves. They were working perfectly, and the burners were just cookin' away
as happy as can be!
Best wishes -
- Vince
Vince Pitelka
Appalachian Center for Craft
Tennessee Technological University
1560 Craft Center Drive, Smithville TN 37166
Home - vpitelka@dtccom.net
615/597-5376
Office - wpitelka@tntech.edu
615/597-6801 x111, FAX 615/597-6803
http://iweb.tntech.edu/wpitelka/
http://www.tntech.edu/craftcenter/
Hank Murrow on wed 3 dec 03
Dear Gordon;
When I sleep, I use an alarm clock to wake me for the next turn up or
cone look.
Cheers, Hank
On Dec 3, 2003, at 5:18 PM, Gordon Ward wrote:
> I too must confess to leaving my gas kiln once red heat is developed.
> My kiln is based on Hank's design which you can practically set your
> watch by. My first version, which I sold about 12 or 15 years ago,
> had a
> mild steel shell. The mild steel throws off heat like mad and the kiln
> room would get quite hot near the end of a firing. The "new" one has a
> stainless shell like Hank's. The difference between the two is
> dramatic. The stainless hardly throws any heat off, keeping the room
> much cooler. This may account for Hank's somewhat relaxed attitude.
>
> Also, about 18 years ago, I fell asleep during a late firing. When I
> awoke (with a start) in the early morning, the kiln was firing merrily
> along at about cone 16. You can imagine how I felt at the sight. The
> stack was a mess and all the pots were completely bloated.
> Amazingly, the kiln was fine! While I would never want to repeat this,
> and I take extreme precautions not to, the experience has given me
> alot of confidence in the design of the kiln.
>
> I still think it's a good idea to stay close and don't go to sleep!
>
> Gordon
>
> _______________________________________________________________________
> _______
> 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.
>
Lee Love on thu 4 dec 03
One of my reasons for building the wood kiln was safety. The kilns here
in Japan typically do not have thermocouples and baso valves.
Of course, there is no way to overfire a woodklin if you fall asleep or go
way for a longer than planned for amount of time.. :^) When you are
near temp, you are stoking about every 3 minutes.
--
Lee In Mashiko, Japan
http://Mashiko.org
Web Log (click on recent date):
http://www.livejournal.com/users/togeika/calendar
John Jensen on thu 4 dec 03
With all this discussion about leaving the kiln while firing, I still do
wonder what others might think about leaving a kiln with just the pilot
light burning.
John Jensen, Mudbug Pottery
mudbug@toadhouse.com , http://www.toadhouse.com
John Britt on thu 4 dec 03
John,
You should never fire a kiln unattended. Even with the thermocouples and
BASO system things can go wrong. I can give you countless stories of
overfiring, explosions, and fires. If you enjoy taking the chance then
that is up to you. There is never a problem until that one time when
there is a problem and you are not there to take care of it. I am sure
everyone here has stories to prove this point. I can even give you stories
of electric kilns overfiring with both a timer and kiln sitter. If you
like to risk burning down the studio or ruining the kiln then that is your
choice.
I just plan to be there during the firing, either working close by or
reading old Ceramics Monthly's while sitting by the kiln. It is a great
way to get an education. And there is no better way to learn about kiln's
and firing than to watch the firing the whole time. You can hear it, smell
it and read the pyromter and cones to your hearts content. You can make
adjustments and watch the reuslts, etc.
Just my two cents,
John Britt
John Jensen on fri 5 dec 03
Vince;
I'm not sure I understand my own concern either. While I have fire the
electric kilns thousands of times, my experience with my gas kiln is
limited. So I have to substitute knowledge of generally accepted
practices in place of my own experience. Hence my questions. But I
must say that while my kiln is firing I don't much want to leave it. I
like to take in the changes and make mental notes or notes in my log.
Right now I am at the end of a sculpture firing...a slightly larger than
lifesize bust. Two days of very careful increases. I did go off and
leave it at times; thanks to the general tone of the advice I've read
lately.
John Jensen, Mudbug Pottery
mudbug@toadhouse.com , http://www.toadhouse.com
Ron Roy on sat 6 dec 03
Hi John,
Interesting to hear so many different attitudes - makes me think - it
depends on how active your imagination is that determins how far you go
away.
If the room is closed - carbon monoxide is a definite possibility - even
with just pilots on.
Then - if the flame goes out and the room fills with gas - well everyone
has enough imagination to figure out what can happen there.
What can go wrong will go wrong eventaully - are baso valves fool proof? Is
there ever enough heat from the kiln to keep one on even after a flame out?
Do they ever stick open? Why is the new standard for open flame burners
shutoff so different now?
I never go far - certainly never drive away - in case something happens and
I can't get back.
If I nap I always use two alarm clocks.
Always watch the CO detector and compare two once in a while to see if they
are comparable.
If a kiln is outside and away from other buildings - and anything else that
can burn - then I would go further. I have a lot or time and effort tied up
in every firing so I like to mind my kiln close - pays off in the end.
RR
>I know and agree that one should be in attendance at all times during a
>gas firing. Tempting as it is sometimes to take run a little errand, I
>always stay on duty. So far so good. But I am wondering what the
>prevailing wisdom about those times when only one pilot light with the
>baso valve/thermocouple is burning would be. Would it be considered
>acceptable to leave such a kiln unattended? What would the risk be in
>that case. Still not something I want to do, but
>hypothetically.........
>
>John Jensen, Mudbug Pottery
>mudbug@toadhouse.com , http://www.toadhouse.com
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513
Earl Krueger on sat 6 dec 03
On Dec 4, 2003, John Jensen wrote:
> I still do wonder what others might think
> about leaving a kiln with just the pilot
> light burning.
2 cents worth from someone who has never
seen a gas kiln close up.
I have been living in my house for 7 years now.
It has a gas furnace and a gas water heater.
Both have a single Baso control unit. I go away
all the time and NEVER turn them off.
Why don't I worry?
Scenario 1: The pilot goes out and the Baso
works correctly. Nothing to worry about.
Scenario 2: The pilot goes out and the Baso
continues to feed gas. Could result in an
explosion. Extremely rare. I take the risk.
So, what's the difference between my furnace
and water heater and a kiln?
Kiln is probably exposed to a harsher environment.
Heat from kiln could radiate back to Baso and
prematurely degrade it. Kilns don't usually have
high temp thermostats to cut off fuel. Kiln temps
are much higher and degrade thermocouples
quicker. Kilns can produce more corrosive gases.
Kilns are low volume manufacturing and don't
warrant as extensive testing and certification.
Homemade kilns MAY not be designed or built
adequately. There are probably more.
Everyone must asses the risks vs. the benefits
and make their own decision. If you do not want
to accept the risk but want to leave, you can lower
the risk by adding a redundant valve in series
with the existing one.
If that wasn't worth your 2 cent investment,
send me a postcard and I will refund.
Earl...
Bothell, WA, USA
piedpotterhamelin@COMCAST.NET on sat 6 dec 03
There are now sensors that you could attach to the pilot light to shut off the gas if the pilot blows out. Although they are used on gas stoves and fireplaces, they are probably adaptable.
--
"Many a wiser men than I hath
gone to pot." 1649
> On Dec 4, 2003, John Jensen wrote:
>
> > I still do wonder what others might think
> > about leaving a kiln with just the pilot
> > light burning.
>
> 2 cents worth from someone who has never
> seen a gas kiln close up.
>
> I have been living in my house for 7 years now.
> It has a gas furnace and a gas water heater.
> Both have a single Baso control unit. I go away
> all the time and NEVER turn them off.
>
> Why don't I worry?
>
> Scenario 1: The pilot goes out and the Baso
> works correctly. Nothing to worry about.
>
> Scenario 2: The pilot goes out and the Baso
> continues to feed gas. Could result in an
> explosion. Extremely rare. I take the risk.
>
> So, what's the difference between my furnace
> and water heater and a kiln?
>
> Kiln is probably exposed to a harsher environment.
> Heat from kiln could radiate back to Baso and
> prematurely degrade it. Kilns don't usually have
> high temp thermostats to cut off fuel. Kiln temps
> are much higher and degrade thermocouples
> quicker. Kilns can produce more corrosive gases.
> Kilns are low volume manufacturing and don't
> warrant as extensive testing and certification.
> Homemade kilns MAY not be designed or built
> adequately. There are probably more.
>
> Everyone must asses the risks vs. the benefits
> and make their own decision. If you do not want
> to accept the risk but want to leave, you can lower
> the risk by adding a redundant valve in series
> with the existing one.
>
> If that wasn't worth your 2 cent investment,
> send me a postcard and I will refund.
>
> Earl...
> Bothell, WA, USA
>
> ______________________________________________________________________________
> 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.
Kathi LeSueur on sat 6 dec 03
erkrueger@EARTHLINK.NET wrote:
> On Dec 4, 2003, John Jensen wrote:
>
>
> 2 cents worth from someone who has never
> seen a gas kiln close up.
>
> I have been living in my house for 7 years now.
> It has a gas furnace and a gas water heater.
> Both have a single Baso control unit. I go away
> all the time and NEVER turn them off.......
>
>
> So, what's the difference between my furnace
> and water heater and a kiln?>>>>>>
The furnace and hot water heater are designed to shut off at a set
temperature. The kiln is not. It will just keep supplying heat. And it
will just keep getting hotter. Eventually, if left alone long enough, it
will melt every thing in it and then it will start to melt the kiln itself.
So imagine this situation: You run out to do a quick errand. The kiln
is at about 1500 degrees. All is well. A drunk comes along and blows you
off the road. You are taken, unconcious, to the hospital. Three days
later you wake up. The kiln is still going because no one knew it was on
or to shut it down.
THAT is the danger of leaving a kiln.
Kathi
>
>
>
Vince Pitelka on sat 6 dec 03
> I'm not sure I understand my own concern either. While I have fire the
> electric kilns thousands of times, my experience with my gas kiln is
> limited. So I have to substitute knowledge of generally accepted
> practices in place of my own experience. Hence my questions. But I
> must say that while my kiln is firing I don't much want to leave it. I
> like to take in the changes and make mental notes or notes in my log.
> Right now I am at the end of a sculpture firing...a slightly larger than
> lifesize bust. Two days of very careful increases. I did go off and
> leave it at times; thanks to the general tone of the advice I've read
> lately.
John -
The decision of whether or not to leave a gas kiln when you are firing
certainly has a lot to do with your own comfort zone. Unless a person has
become very comfortable with their kiln, it probably is a good idea to stay
close by. And some people just love to be around their kiln when it is
firing, especially if they built the kiln themselves. As you know, when a
kiln is filled with the fruits of our hard work and creative capacity, it is
a rather remarkable thing to subject it to the test of the fire.
From my own perspective, I love a very well designed downdraft kiln
operating on venturi or tube burners with natural gas or low-pressure
propane. It is a very quiet kiln, and you can often detect the "rumble" of
the flames combusting and moving inside the kiln, especially during
reduction. It is like a living entity, and I always feel energized in its
presence. Such a kiln is so easy to control, because with experience we
become so sensitive to the sound of the kiln, the shape of the flame at the
burner ports, the appearance of flame in the damper slot, etc. - so many
things in addition to back pressure and cone indications. We develop such a
symbiotic relationship with our kiln, and that can be a very magical thing.
The studio potter who develops such a relationship with her/his kiln and
firing processes is going to have a much higher rate of success and a much
higher occurence of "racers," as Tony Clennell calls them.
Best wishes -
- Vince
Vince Pitelka
Appalachian Center for Craft
Tennessee Technological University
1560 Craft Center Drive, Smithville TN 37166
Home - vpitelka@dtccom.net
615/597-5376
Office - wpitelka@tntech.edu
615/597-6801 x111, FAX 615/597-6803
http://iweb.tntech.edu/wpitelka/
http://www.tntech.edu/craftcenter/
Vince Pitelka on sat 6 dec 03
> There are now sensors that you could attach to the pilot light to shut off
the gas if
> the pilot blows out. Although they are used on gas stoves and fireplaces,
they are
> probably adaptable.
Isn't this just a the standard thermocouple and Baso valve that you are
talking about? If so, we have been discussing them for the past few weeks
here. The only other standard system is the "fire eye" flame rectification
system, which is far more complex and expensive, generally only used on
industrial and institutional installations.
- Vince
Vince Pitelka
Appalachian Center for Craft
Tennessee Technological University
1560 Craft Center Drive, Smithville TN 37166
Home - vpitelka@dtccom.net
615/597-5376
Office - wpitelka@tntech.edu
615/597-6801 x111, FAX 615/597-6803
http://iweb.tntech.edu/wpitelka/
http://www.tntech.edu/craftcenter/
John K Dellow on sun 7 dec 03
Kathi ,
the pressure at which the burners are set also comes into the equation.
A for instance is my terra-cotta kiln . I use low pressure and take a
long time to fire.
The max I use is 22 kpa. I did once forget to turn my small kiln off one
evening .
This kiln was being fired 7 days a week at the time .
I would get up at 5am ,crack the door then have breakfast. Unpack and re
load before 7 am and fire to
7 pm. I for got to turn it off one evening and got a shock at 5 am the
next morning :). It was being
fired to C3 and the pyro read 1250 c ,but the terra-cotta was just
darker than usual. Probilly a bit
brittle and of course I had to sell the load as seconds.
John
>>
>
>
> The furnace and hot water heater are designed to shut off at a set
> temperature. The kiln is not. It will just keep supplying heat. And it
> will just keep getting hotter. Eventually, if left alone long enough, it
> will melt every thing in it and then it will start to melt the kiln
> itself.
>
> So imagine this situation:
John Dellow "the flower pot man"
From the land down under
Home Page http://www.welcome.to/jkdellow
http://digitalfire.com/education/people/dellow/
piedpotterhamelin@COMCAST.NET on sun 7 dec 03
Lately, I have been researching the direct vent and non-venting gas heaters for use in my studio. These affordable stoves have a sensor that detects if the flame is absent at the pilot and shuts down the valve. I cannot conclude their adaptability to our use but I believe that they are more affordable priced compared to the industrial versions. This I believe is the fire eye that you refer to, but I really don't know. Many new kitchen stoves have the same feature. The question is would these home appliance rated systems work on some kiln burner systems? They could be more reasonably price or scavanged from a old stove. Ideally, it would be great if it could also be connected to an alarm to alert us when the pilot dies.
By the way, from what I learned concerning the non-venting gas heaters, they are not safe for pottery studio use. They rely on a CO2 sensor to prevent toxic levels from being reached. This sensor MUST BE KEPT FREE FROM DUST. So beware if you are using one. The dust issue is what makes these heaters ILLEGAL in Massachusetts and other states.
I just back to ClayArt and have been skipping around on the threads and didn't see the initial posts. Finally have my new studio up and have been busy with my wife putting in windows and putting up the siding and installing the wood stove. Should be throwing in it by March.
18 inches of snow in the driveway. Time to get out there and clean it
Happy season to all
Rick
--
"Many a wiser men than I hath
gone to pot." 1649
> > There are now sensors that you could attach to the pilot light to shut off
> the gas if
> > the pilot blows out. Although they are used on gas stoves and fireplaces,
> they are
> > probably adaptable.
>
> Isn't this just a the standard thermocouple and Baso valve that you are
> talking about? If so, we have been discussing them for the past few weeks
> here. The only other standard system is the "fire eye" flame rectification
> system, which is far more complex and expensive, generally only used on
> industrial and institutional installations.
> - Vince
>
> Vince Pitelka
> Appalachian Center for Craft
> Tennessee Technological University
> 1560 Craft Center Drive, Smithville TN 37166
> Home - vpitelka@dtccom.net
> 615/597-5376
> Office - wpitelka@tntech.edu
> 615/597-6801 x111, FAX 615/597-6803
> http://iweb.tntech.edu/wpitelka/
> http://www.tntech.edu/craftcenter/
>
> ______________________________________________________________________________
> 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.
Earl Krueger on sun 7 dec 03
On Sunday, Dec 7, 2003, at 09:38 US/Pacific,
piedpotterhamelin@COMCAST.NET wrote:
> with my wife putting in windows and putting up the siding and
> installing the wood stove.
Rick,
If you ever get tired of that wife, let me know. She sounds like a
"Racer" to me! ;->
Earl...
Bothell, WA, USA
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