william schran on fri 22 oct 04
I will soon be getting a model 2327 Olympic gas kiln set up and have
read through information gathered from the archives concerning the
shelf positioning & firing of this kiln.
One thing that I read concerns the positioning of the bottom shelf.
Either use a full shelf or the 2 half shelves and block the middle
above the center burner to better disperse the heat. What about the
distance between the shelves, how far apart?
I'm wondering, would it make sense to stagger the orientation of the
half shelves as they are built up in the kiln? If the bottom two
shelves were set so the gap was aligned north/south, would it make
sense to align the next set eats/west to better disperse the heat? Or
should all the shelves be aligned the same direction?
Thanks for your insights, Bill
George Nagel on fri 22 oct 04
Hello Bill, I've been emailing with a number of people about this kiln the=
past couple of weeks. I've received a lot of good ideas and information. =
My experience to date is that Olympic's instructions are not totally usefu=
l. To be truthful, I've never really fired this kiln with their recommenda=
tion of keeping the bottom shelves spread and allowing the flame to go up t=
he middle of the kiln. In their latest instructions (They've changed them =
in the past year) They talk about rotating the shelves around as you stack.=
I've not done that, but it would be an interesting experiment. Perhaps I=
'll try that after awhile after I've had some consistent satisfactory firin=
gs. I'm getting there. Most people I've talked with use a full shelf on t=
he bottom. I suspect they've gone with that by experience. I'm allowing a=
half inch spread on the bottom shelves. However, I have the bottom shelve=
s 4 inches off the bottom and at 3 " I've place a small piece of kiln shelf=
directly over the central burner. Deflecting the flame to the sides of th=
e kiln where there aren't burners. I've talked with people who use a full =
shelf on the bottom that direct the flame that way using a brick arrangemen=
t under the shelf that forces the flame to the sides. Otherwise, I stagger =
and spread the remaining shelves as I go up. I'm spreading the upper shelv=
es about an inch and staggering them somewhere around 2 plus inches.
Allowing room for circulation seems important. I'm firing in reduction, so=
this is even more important to try to get even reduction than even tempera=
ture I think.
Not sure how you're getting your kiln set up. Make sure that you have ampl=
e gas pressure/the right regulators for the set up if you fire with propane=
. I'm firing with propane and I've had to do some adjustments to get it se=
t up right. Initially I just assumed the propane people would know what to=
do if I gave them the requirements. Not so here.
Another thought. Olympic seems to imply that you don't have to damper down=
the exit flue much to get good reduction. That hasn't been my experience.=
To get a good reduction I have to close it off quite a bit. I set the bu=
rners at set up time and don't mess with the primary air adjustments. Go w=
ith dampering the flue and gas flow in doing the body and glaze reduction. =
Pretty much everyone I talk with recommends the same thing.
I recently had some problems with glazes bubbling and looking underfired af=
ter cone 10. Advice was to slow down the fire, rate of climb. That has tur=
ned out to be very good advice.
Probably more I could say, let me know if you have any further questions. =
Good luch. George
-----Original Message-----
From: william schran
Sent: Oct 22, 2004 7:02 AM
To: CLAYART@LSV.CERAMICS.ORG
Subject: small updraft gas kiln question
I will soon be getting a model 2327 Olympic gas kiln set up and have
read through information gathered from the archives concerning the
shelf positioning & firing of this kiln.
One thing that I read concerns the positioning of the bottom shelf.
Either use a full shelf or the 2 half shelves and block the middle
above the center burner to better disperse the heat. What about the
distance between the shelves, how far apart?
I'm wondering, would it make sense to stagger the orientation of the
half shelves as they are built up in the kiln? If the bottom two
shelves were set so the gap was aligned north/south, would it make
sense to align the next set eats/west to better disperse the heat? Or
should all the shelves be aligned the same direction?
Thanks for your insights, Bill
___________________________________________________________________________=
___
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.
| |
|
