Polly Goldman on tue 11 may 99
Hi Clay Arters,
I'm new to this list, and the amount of knowledge I've seen here so far has
inspired me to seek help from you all.
I was given a 16 cu.ft. updraft gas kiln a few years ago - manufacturer
unknown, about 20 years old, used regularly for ^6 firings. I finally got
it set up at my house on natural gas, and tried to fire it last weekend,
but couldn't get it to ^10. It got to a nice orange sherbet color inside
the kiln, and then stopped. I've poured over Olsen's Kiln Book - the gas
pressure, volume, and orifice sizes should be okay. I fired it a couple of
times on propane a year or so ago, and so know it has the capability to get
to tempurature. What could I be missing? Possibilities I've thought of
are:
- I loaded the kiln very lightly; could this be enough to prevent it from
getting to temp?
- The actual BTUs going through the kiln were quite a bit more than it
actaully needed. I thought that it might not be getting enough primary O2
for all this gas, but have tried adjusting the bottom rings on the burners
and the flame did not seem to be affected at all. Could the orifices be
too big (even though they are the recommended size of 32 gauge)?
- I forgot to put the kiln god/dog on the kiln when I set it up at my
house. Could this be it?
Any suggestions would be most appreciated.
Polly Goldman
dave morrison on wed 12 may 99
without a kiln god, anything is possible, but you may not have enough gas
pressure. the gas company may have to come and install a new regulator for
you. this happened to me where i used to work.
-----Original Message-----
From: Polly Goldman
To: CLAYART@LSV.UKY.EDU
Date: Tuesday, May 11, 1999 10:57 AM
Subject: stubborn kiln
----------------------------Original message----------------------------
Hi Clay Arters,
I'm new to this list, and the amount of knowledge I've seen here so far has
inspired me to seek help from you all.
I was given a 16 cu.ft. updraft gas kiln a few years ago - manufacturer
unknown, about 20 years old, used regularly for ^6 firings. I finally got
it set up at my house on natural gas, and tried to fire it last weekend,
but couldn't get it to ^10. It got to a nice orange sherbet color inside
the kiln, and then stopped. I've poured over Olsen's Kiln Book - the gas
pressure, volume, and orifice sizes should be okay. I fired it a couple of
times on propane a year or so ago, and so know it has the capability to get
to tempurature. What could I be missing? Possibilities I've thought of
are:
- I loaded the kiln very lightly; could this be enough to prevent it from
getting to temp?
- The actual BTUs going through the kiln were quite a bit more than it
actaully needed. I thought that it might not be getting enough primary O2
for all this gas, but have tried adjusting the bottom rings on the burners
and the flame did not seem to be affected at all. Could the orifices be
too big (even though they are the recommended size of 32 gauge)?
- I forgot to put the kiln god/dog on the kiln when I set it up at my
house. Could this be it?
Any suggestions would be most appreciated.
Polly Goldman
Marc Ward on wed 12 may 99
Polly,
You gave us quite a bit of info on your kiln....unfortunetly some of it
contradictory. Technical issues like this can be batted around forever with
electrons on a computer screen. I could pose a longer list of questions for
you. Because of this, you need to call to hash this out. Look forward to
hearing from you.....
Marc Ward
Ward Burner Systems
PO Box 333
Dandridge, TN 37725
USA
423.397.2914 voice
423.397.1253 fax
wardburner@aol.com
fox hollow on wed 12 may 99
Dear Polly:
I have a 12 cu. ft. Olympic kiln that gave me FITS for several years. I could
have fired it for 10 years and it wouldn't have gotten up to temperature.
I DO think the kiln should be stacked full, that it needs the bodies in it to
keep it hot. Some other possibilities: You may not have the baffle shelf in
(appx. 1-1/2" from top). You may be stalling the kiln by having it in too much
reduction. The magic trick for me (THIS IS ASSUMING YOUR BURNERS ARE ON THE
FLOOR OF THE KILN) was to split my first bottom row of shelves and bring them
half way over the burners, so that the flames were forced to the inside. The
next highest row, I did the same. The third highest row, I closed the shelves
back together. Another thing, I was firing my taller pieces (9" to 12") on the
bottom shelf. Now, I am convinced that this shelf needs to be saved for my
mugs and bowls (5" to 6"). This may not help you at all, but has worked for
me. My potter friends gave me lots of advice and support during this trying
time. GOOD LUCK.
I'll be at a show for about a week, so won't see any e-mails in case you want
to discuss this further.
Yours for fine crafts,
Jean Cochran
Fox Hollow Pottery
Polly Goldman wrote:
> ----------------------------Original message----------------------------
> Hi Clay Arters,
> I'm new to this list, and the amount of knowledge I've seen here so far has
> inspired me to seek help from you all.
> I was given a 16 cu.ft. updraft gas kiln a few years ago - manufacturer
> unknown, about 20 years old, used regularly for ^6 firings. I finally got
> it set up at my house on natural gas, and tried to fire it last weekend,
> but couldn't get it to ^10. It got to a nice orange sherbet color inside
> the kiln, and then stopped. I've poured over Olsen's Kiln Book - the gas
> pressure, volume, and orifice sizes should be okay. I fired it a couple of
> times on propane a year or so ago, and so know it has the capability to get
> to tempurature. What could I be missing? Possibilities I've thought of
> are:
> - I loaded the kiln very lightly; could this be enough to prevent it from
> getting to temp?
> - The actual BTUs going through the kiln were quite a bit more than it
> actaully needed. I thought that it might not be getting enough primary O2
> for all this gas, but have tried adjusting the bottom rings on the burners
> and the flame did not seem to be affected at all. Could the orifices be
> too big (even though they are the recommended size of 32 gauge)?
> - I forgot to put the kiln god/dog on the kiln when I set it up at my
> house. Could this be it?
> Any suggestions would be most appreciated.
>
> Polly Goldman
Katie Cordrey on wed 12 may 99
I don't' have tons of experience, but if the flame is not blue, it is likely
not getting enough oxygen. Are your burners spaced back from the ports
correctly? There should be between 1/4" and 1" gap to create the venturi
necessary. And you DID have the orifice re-sized, right? I lived without
electricity for years, so know that gas and propane will not work properly
with the same size orifice. Natural gas has to be larger.
-----Original Message-----
From: Ceramic Arts Discussion List [mailto:CLAYART@LSV.UKY.EDU]On Behalf
Of Polly Goldman
Sent: Tuesday, May 11, 1999 8:57 AM
To: CLAYART@LSV.UKY.EDU
Subject: stubborn kiln
----------------------------Original message----------------------------
Hi Clay Arters,
I'm new to this list, and the amount of knowledge I've seen here so far has
inspired me to seek help from you all.
I was given a 16 cu.ft. updraft gas kiln a few years ago - manufacturer
unknown, about 20 years old, used regularly for ^6 firings. I finally got
it set up at my house on natural gas, and tried to fire it last weekend,
but couldn't get it to ^10. It got to a nice orange sherbet color inside
the kiln, and then stopped. I've poured over Olsen's Kiln Book - the gas
pressure, volume, and orifice sizes should be okay. I fired it a couple of
times on propane a year or so ago, and so know it has the capability to get
to tempurature. What could I be missing? Possibilities I've thought of
are:
- I loaded the kiln very lightly; could this be enough to prevent it from
getting to temp?
- The actual BTUs going through the kiln were quite a bit more than it
actaully needed. I thought that it might not be getting enough primary O2
for all this gas, but have tried adjusting the bottom rings on the burners
and the flame did not seem to be affected at all. Could the orifices be
too big (even though they are the recommended size of 32 gauge)?
- I forgot to put the kiln god/dog on the kiln when I set it up at my
house. Could this be it?
Any suggestions would be most appreciated.
Polly Goldman
CNW on thu 13 may 99
Polly- there is a difference in the size orifice needed for propane and
natural gas. That might be causing the problem. Check with your gas
supplier. If that is your problem it is relatively inexpensive and easy to
fix.
Celia-in NC just in from trimming hooves and jogging ponies.
Polly Goldman on thu 20 may 99
Thanks a million to all who responded to my earlier post about not being
able to get my kiln up to tempurature. I just wanted to let you know that
**I fired it successfully last weekend!!** I'm totally psyched, as they
say...
Here's what I did: I drilled out the orifices to a bunch of different
sizes, from 32 (recommended, and usually supplied, for use with natural
gas) to 38 (recommended for propane), put a different size in each burner,
then turned on the gas. The 36 had the nicest looking flame, so I used
that size for all burners (well, five of the six, since by then I was out
of orifices, and couldn't find a supplier anywhere in Santa Cruz. For the
6th one, I used a size 34. Anyone know where to buy orifices in Santa
Cruz?)
Then I packed the kiln pretty full, moving the shelves outwards to partly
block the flames from just going directly out of the kiln, and put in a
large shelf at the top for a baffle. As soon as the kiln got pretty hot, I
closed up the damper until flames came out of the kiln and I could smell
gas and then sulfur, to know I was reducing, and then opened the damper up
again until just the point that the flames and smell went away. I had
tried this before, but never got to the point of reduction -- the damper
was almost COMPLETELY closed before reduction happened, which I didn't
expect.
And the tempure kept going up until the little cones just sagged over.
What a lovely sight!!!
Again , thanks for all your suggestion. I like this list!
Polly Goldman
June Perry on fri 21 may 99
Dear Polly:
Just look in the Yellow pages under Propane. Propane dealers will carry the
orifices.
Regards,
June
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