Time to Leap

 

IT IS TIME TO LEAP

 

 

 

After a number of years working on glazes and technique, it is time for me to post some of my work again. I have a new web site made by fellow potter Wayne Bates, and am trying out etsy. The links are as follows:

 

www.lizgowen.com      website and

 

lizgowenpottery@etsy.com

 

 

I have been leaning to fire a reduction kiln, working on getting some copper reds at ^6 reduction as well as copper blues ^6 oxidation. I have also been on a quest as to how I wish to finish my carved porcelain nature pieces. I think I like the inlaid slip and underglazes. There will be more to come but thought I would launch these today, my birthday, since I guess there will always be just one more picture! Please take a look and enjoy.



kiln II copper reds O

the new kiln

The new kiln is here and installed and I did the first firing yesterday of copper reds of course. They came out green again. I am posting pictures of the kiln and the pots since I just don't know what to try next. One change is my oxyprobe from my other kiln is only 8 inches and this one needs 12 inches which will cost 999.00. without the box.

It was a 12 hour firing going up 350F per hour for the 1st 3 hours then with increases of 1"wc it started to go only 200 then 100 then had to be increased 1" per half hour to get a better rate of climb. I had the damper at 2 on the Geil 12cuft fiber kiln. When I pushed it in to 1 3/4 the temp started to drop so I put it back near 2. Each time I checked the spy holes it lit paper or weeds at about 2 inches but I never saw a flame or smelled the reduction smell. any suggestions would be apprecaited. DO I need to reglaze some of the less green pieces? The one white piece has already been through 2 firings ( one in the old kiln)

A new kiln in the works

After all my efforts with my Broadnax kiln I decided to help me get more consistent copper reds I was going to take the leap and get a new kiln. I have been in the process of getting and installing it. It seems to take forever sometimes when you have to relay on others to get the work done. I think I am almost ready for the 1st shelf firing then a glaze. The pots have been waiting for months. stay tuned.

3rd copper red firing11/9/09

For the third firingI staggered the shelf height hoping for more heat in the upper area. Marked the shelf used as the damper in 1/2" increments so could see a measurable amount of closure produced how much reduction. Was able with this to fire with less gas only needed to go to 2 on my dial instead of 9 to get reduction could make the kiln climb with a 100 to 300 degree difference between the bottom and the top temperature probe. was able to keep the oxyprobe at between 0.60 and 0.65 for most of the firing going up after hitting 1600 BUT had a brain fart and moved my decimal point and thought it should have been 6.5 not 0.65 so had turned off the burners at between 1800 bottom and 1500 top just leaving the pilots on thinking I was going to stop it when my error hit me and I put the burners back on after 5-10 min. The rest of the firing going up was in reduction. I let the bottom temp probe go as high as 2330 but stopped because I couldn't get the top above 2000 . I decided to try to let the temp drop to around 1900 and held it there for 45 min and lowered it slowly another couple hundred degrees with low burners then the pilots then shut it down stuffed the fireports with fiber ans well as covering over the draft hole in the top with fiber. Results: cone 10 on the lowest staggered shelf cone 9 the next, six inches higher not even a cone 8 and the top shelf not even a cone 6 The copper......was green Did I ruin the reduction when I turned it off even though when I restarted and the rest of the firing up it was a 0.65 on the oxyprobe? By slow cooling in oxidation did it turn back to green and loose the reduction ? If so how can I slow cool and reduce. The damper was closed except for I guess some leaks I couldn't get it to reduce on the way down. I was able to get the kiln to rise and even made it stall and then rise again by manipulating the damper and the gas pressure. Any thoughts appreciated. Thinking may need to rebuild the exit flue area to get it tighter, Any one know the shelf that can take the hottest temps so I could use it on the bottom and take it hotter the soaps can go hotter, or a way to get more heat to the top shelves before it exits. I restuffed all the cacked areas in the fiber and may calmp the door tighter. Please feel free to comment on clayart Thanks Liz

2nd copper red firing

Second firing of copper reds in gas kiln. Got new shelves and soaps for the lower level of the kiln since this gets so hot. Raised the first shelf up to full soap height. Fired again trying to slow down the firing but was unable to get the kiln into reduction by 1650 F so ended up with all copper greens. Cooled too fast and some pots were broken. Top again no cones melted in 8/9/10 pack bottom shelf ^10 melted.

Kiln firing schedule How to even out?

0645: pilots lit door open
0630: pilots upper temp 220 lower 220
0645: pilots upper 384F Lower 557F smell wax bur off
0720: pilots upper 447F Lower 594
0742 pilots upper 549F Lower 656F firing smell
0820 pilots upper 686F Lower 709F Turn on burners 0.5 blue flame
0844 Upper 1007F lower 1322F oxyprobe 0.03 move damper in 1 inch
0900 upper 1144F lower 1457F oxyprobe no reading put piece of fiber over 1/2 of burner port entrance each side to block 2ndary air.
0930 upper 1288F lower 1563F damper in another inch upped gas to 2.0 no oxy readout.
0940: upper 1388F Lower 1716F gas to 5
0945: upper 1521F lower 1985 oxy .08-.09 covered flue 1/2 increased gas to 9
1015: upper 1997 LowerOL switched to C oxy .68 redux smell
1020: upper 1123 C Lower 1378 oxy .68 cones unmelted inside kiln orange.
1030: upper 1150C lower 1405C oxy .62 cones not bent
1047: upper 1199C lower 1361C oxy .26 increased gas to 10
1055 looked at cones saw R shelf had fallen followed by left shortly after.
Turned off kiln allowed to crash cool to touch in about 4 hours.

1ST solo gas firing copper reds