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reducing fibre kiln

updated thu 4 nov 04

 

dneese on wed 3 nov 04


Although my kiln is not fibre I had trouble with uneven reduction in a few
areas of my Olsen updraft. I suspected the secondary air from around the
burner ports were letting in too much air. I probably cut them a tad too
large when first building the kit. I had already adjusted the primary air
shutters on the burners down to about as far as they would go without much
change in the fired glazes and was almost thinking that this would be the
usual firing. Then I placed small slices of firebrick in the ports to
slightly cut down on the amount of secondary air entering around the burner
ports. It worked for me last two firings when all of the pots were evenly
reduced in most problem areas of the stack. I also started reduction at cone
010 instead of 09. There are two burners under the bottom middle shelf of my
updraft which are not turned on until later in the firing. I now just barely
turn them on earlier in the firing eliminating some more of the colder air
coming in. All my damper settings remained the same. Firing sure was
frustrating for a while before finding this "cure".

Dale Tex
"across the alley from the Alamo"
San Antonio, Texas USA