bill bosworth on sun 25 aug 96
Hi it's me again with another question about my salt kiln...I have read all
the books out there about kiln building. I just want different opinions
from people who have done it before and learned from their experiance.
Where do I put the burners? How many rows from the floor of the kiln? I
will probably use 8 venturie burners in a kiln that is 54" x 45" x 58 1/2"
inside. Thank you!!
Tom Gray on sun 25 aug 96
Hi it's me again with another question about my salt kiln...I have read
all the books out there about kiln building. I just want different
opinions from people who have done it before and learned from their
Heather-Why not keep things simple. Two burners on either side of the
chimney firing toward the front of the kiln. Works for me and the
majority of potters I know-here in Seagrove and elsewhere. All the
potters that use multiple burners (at least the kilns I have seen here)
have massive kilns. These kilns are approx. 8 ft. wide-minimum of 6 ft.
tall and 8 ft. deep! One of the kilns here in Seagrove requires a ladder
to be loaded! Unless your kiln is pretty large-a 2 burner arrangement
means less money in burners initially-and less stuff to maintain. It
also makes firing simpler-esp. if you use a manifold leading into both
burners off of one control valve. Of course-you have to have a separate
cut-off for both burners. My car kiln is the same dimensions as the kiln
in your posting. I use 2 Big Bertha burners available from L.B. White
(purchased from your local agricultural supply or gas co.). This system
was shown to me by Tom Turner and is also used by Ellen Shankin. Good
Randy Brodnax on sun 25 aug 96
Where to put burners? I would put them on the sides of the kiln.
One burner to one port. Do not place burners inside of ports. Leave
burners approximately two inches outside of port. It's amazing how
important the secondary air is.
How many rows from the floor? At least two rows (5 in.), preferably
three (7.5 in.). That is if you're using standard size brick, 9" x
4.5" x 2.5". It would help if you had a foundation of cinder block,
one or two rows, between the floor of the kiln and concrete slab.
Number of burners? Eight sounds like too many. I think six would be
sufficient. There are formula's for determining burner's and orifice
size. See Lou's "The Art of Firing" or call Marc Ward. Mr. Ward is
very knowledgeable and quite helpful.
Type of burners? In my experience, venturi's are a bad idea for
what you have in mind. I would make pipe burners from two inch
plumbing pipe. The plans are in Rhodes, Olsen's, and Lou's books.
Source of sodium? I prefer soda ash (sodium carbonate). I mix three
pounds of soda ash and half pound of borax. This is put into 1.5
gallons of water.
Soda into to kiln (I hate to use the term introduction of soda to
kiln. It reminds me of Ralph Kramden telling Ed Norton to address
the ball). I use a garden sprayer with a brass wand. I believe this
to be the most efficient method for putting soda into kiln. My last
firing I only used half of solution, approximately 1.5 pounds of soda
Other firing tips. You can pack the kiln tightly with ware. Wait
until the maturing temp of clay/glazes before salting. If you salt
earlier you might stall kiln. It's not necessary to close damper
when salting. Vapor distributes throughout chamber fine with damper
open. Use test rings (raw clay, no slips or stains on rings) to
measure amount of salt accumulation. Use cones to measure temp.
They're not completely accurate because of vapor, but they help. You
don't have to fire to cone 10-11. Stoneware clays mature starting at
cone six. I fire to cone 7-8. This is the temperature the clays,
slips, and glazes I use mature. I feel the kiln will last longer if
not taken to cone 10-11. After final salting, continue to fire
approximately 30 minutes. Good luck!
Cedar Valley College
>>> bill bosworth 8/25/96, 06:07pm >>>
Hi it's me again with another question about my salt kiln...I have
read all the books out there about kiln building. I just want
different opinions from people who have done it before and learned
from their experiance.
Where do I put the burners? How many rows from the floor of the
kiln? I will probably use 8 venturie burners in a kiln that is 54" x
45" x 58 1/2" inside. Thank you!!
firstname.lastname@example.org on mon 26 aug 96
I second this configuration of two burners from the rear on either
side of the chimney. Works for me at MSU-B. I've used this on all
the kilns I've built here for over 20 years and I use big berthas, too.
Our largest kiln is 60 cu ft. BUT when planning your flu remember
high altitudes need more draw. A perfect copy of an Olsen woodfired
kiln at Banff did not draw because it was over 6,000ft. above sea level.
If your at a high altitude keep that in mind. We're over 3,000 ft. in
Billings so I always add a little more height than the rule of thumb.
I test the draw with burning newspaper. If the ashes get sucked up
the chimney then that's high enough.If not, keep adding height 'til
they do. A good draw makes the kiln easy to control and get even firings
and even reduction.
Marcia Selsor, Montana State University_Billings