Hank Murrow on fri 17 aug 01
>My downdraft, 30 cubic ft. propane gas kiln is firing to cone10 but hot at
>the bottom and cold at the top often cone 11-12 in the bottom half of the
>kiln and cone 9 to barely 10 near the top. WHAT ARE SOME OF THE
>ADJUSTMENTS IN BAG WALL, SHELVING ETC THAT HAVE HELPED IN EQUALIZING
>TEMPERATURE??
>
Suggest you tighten and/or raise the bagwall. Not much else to say until
more information is supplied.
Hank
EDGOULD on fri 17 aug 01
My downdraft, 30 cubic ft. propane gas kiln is firing to cone10 but hot =
at the bottom and cold at the top often cone 11-12 in the bottom half =
of the kiln and cone 9 to barely 10 near the top. WHAT ARE SOME OF THE =
ADJUSTMENTS IN BAG WALL, SHELVING ETC THAT HAVE HELPED IN EQUALIZING =
TEMPERATURE??
Marcia Selsor on sat 18 aug 01
I'd say use your damper more, but it is hard to know without knowing the
existing bagwall, shelving etc configuration. I usually stack a 9" shelf
on the bottom layer, go dense in the middle front and put the tallest
peices tightly on top. Sometimes if the bottom is short and tight, it
can choke the circulation. (my experience with my old kilns). I had 2
burners on a 40+ cubic foot downdraft coming from the rear. They aimed
into target bricks at the other end of the kiln outside the bag wall.
The inside of the bagwall was exposed about 2 " on either side of two
shelves and about 1" in between. Usually the top would get hot first and
then in body reduction it would even out.
Use your damper to force the heat up in a down draft. You should be
getting a hard short flame out the top peep. The bottom peep should have
a gentle licking flame if you are forcing things to the top.-my
experience.Everyone's is particular to their kiln.
Marcia in Montana
EDGOULD wrote:
>
> My downdraft, 30 cubic ft. propane gas kiln is firing to cone10 but hot at the bottom and cold at the top often cone 11-12 in the bottom half of the kiln and cone 9 to barely 10 near the top. WHAT ARE SOME OF THE ADJUSTMENTS IN BAG WALL, SHELVING ETC THAT HAVE HELPED IN EQUALIZING TEMPERATURE??
>
> ______________________________________________________________________________
> 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.
--
Marcia Selsor
selsor@imt.net
http://www.imt.net/~mjbmls
http://www.imt.net/~mjbmls/May2001.html
http://www.imt.net/~mjbmls/Tuscany2001.html
http://www.imt.net/~mjbmls/Gallery.html
Marvpots@AOL.COM on sun 19 aug 01
Try placing a target brick at the end of each bag wall so as to deflect the
flame upwards. Placing the brick at a 45 degree angle might be your first
attempt; if that is too severe, just place the brick at a 90 degree angle to
the floor. This should give you more even heat distribution.
Let me know how you make out.
All the best.
Marvin Flowerman
marvpots@aol.com
| |
|
