OCTOBER 12 KILN FIRING 2010 -- cone 6 2232 F

MOST OF THE PIECES ABOVE HAD THE GLAZE BRUSHED ON WITH A HAKE BRUSH.  EVEN THOUGH I TRIED TO BE SURE AND BRUSH THE GLAZE ON VERY THICK, STILL A FEW OF THEM WOUND UP BEING TOO THIN IN PLACES -- with the exception of Heidy's Eggshell, which just does good no matter what you do to it.

Still, the pieces came out with nice bright colors. Although there was an issue with thinness in places due to brush application, basically, it was a good firing and I learned a LOT from it.

ACTUAL FIRING RAMP note: kiln lid was cracked open for 14 hours of firing. it was 1900 degrees when Jen closed it. My bad. Hence the ramp was slowed to about 150 degrees per hour for 14 hours. Maybe more

200 degrees an hour up to 2100

100 degrees an hour up to 2232

-- Hold 8 minutes

drop at full speed to 1800
100 degrees an hour down to 1300

Again, HEIDY'S EGGSHELL GLAZE performed admirably.  It did not mind the slow cool at all. The colors are fresh and gorgeous.  The glaze came out very even.  I found that the areas where it is thinner are where the lovely rusty tones come out.

EGGSHELL -- tried and true from Ceramic Arts Daily

CONE 6	X1	X2	X3	X5
Whiting	9.5	19	28.5	47.5
Zinc Oxide	5.5	11	16.5	27.5
Frit 3124	44.5	89	133.5	222.5
Custer Feldspar	20	40	60	100
Bentonite	7.5	15	22.5	37.5
Kaolin	5	10	15	25
Silica	8	16	24	40
TOTAL	100	200	300	500
OXIDES
Tin Oxide	9	18	27	45
RIO	3	6	9	15

DJ'S GRAPE GLAZE

The Grape glaze with cobalt carbonate came out a perfect purple -- even better than the same recipe using cobalt oxide.  Jen said that this was the first time she'd seen a glaze come out actually purple instead of dark blue. She said, "That's DJ's Purple" -- I'll check to make sure its not just a derivative of Jeannie's purple.  If it isn't, then I guess its DJ's purple all right! I'm pretty sure the great color is due to the slow cooling at 100 F an hour from 1800 to 1300 degrees. It brings out more red.

DJ's GRAPE GLAZE WITH COBALT CARBONATE

cone 6	X1	X2	X3	X5
Neph Sy	18	36	54	90
Frit 3134	14	28	42	70
Whiting	20	40	60	100
OM4	18	36	54	90
Silica	30	60	90	150
total	100	200	300	500
oxides
Chrome Ox	0.2	0.4	0.6	1
Tin Ox	7.5	15	22.5	37.5
Cobalt Carb	1	2	3	5
RIO	0.5	1	1.5	2.5

RASPBERRY BLUE BUST!

Alisa Clausen's Raspberry blue, whose image I loved so much and researched so hard to mix correctly turned out to be a bust.  It's a glossy, watercolory sort of glaze that looks like diltued cobalt blue -- its cool if you want that sort of effect -- but I didn't want it.  I'll try it again dipped, but I think its just going to be a translucent cobalt blue.

Here's the pic from Alisa Clausen's flickr

CONE 6	X1	X2	X3	X5
Neph Sy	18	36	54	90
Frit 3134	14	28	42	70
Whiting	20	40	60	100
OM4	18	36	54	90
Silica	30	60	90	150
total	100	200	300	500
oxides
Cobalt Carb	1	2	3	5
R I O	0.5	1	1.5	2.5

Well, they are both blue, that's for sure.  I like seeing the glaze on an entire piece rather than a small rectangle of it.  I'll make sure that I mixed it right, but after mixing it three different times, I'm pretty sure that I did. Anyway, I don't like how it turned out.  I'll try it a couple more times, put on thicker and also try it on a couple of different clay bodies.  But so far, its a "meh."

PRAESYODIMIUM YELLOW GLOSS

The praesyodimium yellow gloss came out muddy looking onf the buff clay that I've been making Laszlo's bowls out of.  It looks great on the white clay body next to it.  SO I'll make some bowls of Cinco Blanco and try it on that.  I also am going to try it with a bit of tin in it as an opacifier,  In the gloss white base, its quite translucent, so the buff claybody cannot work well with it if you want a pure yellow. 

Neph Sy	35
Silica	21
EPK	10
Whiting	8
Gerstley Borate	18

COLORANT: add 7 grams of praesydimonium yellow

AMACO VELVET UNDERGLAZE CHARTREUSE 

WITH K-17 CONE 6 GLAZE ON TOP

This color is for one of the marine monster jugs that I have made.  I like the effect of the k17 on top of the chartreuse.  I'll have to get the K-17 recipe from my google docs excel files of the school's cone 6 glazes.  It's nice the way it highlights the texture on the right teabowl.

JOHN POST'S TOMATO RED 13 AND JUICY FRUIT VARIANT

Where it was put on thick enough, it came out great.  On the mug below, its mediocre.  I'll mix up more next time around and and put it on THICK! This glaze should probably be dipped, not brushed on.  Where you see it come out so nicely on the above piece is where I dipped it in the small amount that I mixed up.

John Post Tomato Red #13

FRIT 3134	10.8
Neph Sy	23.1
Bone Ash	10
Magnesium Carb	6.2
Whiting	7.7
EPK	21
FLINT	21.2
TOTAL	100
BENTONITE	2
Red Iron Oxide	12
Lithium Carb	2

JEN'S JUICY FRUIT VARIATION FROM JOHN POST -

CONE 6	X1	X2	X3	X5
EPK	30
Gerstley Borate	27
Neph Sy	147
Flint (Silica)	36
Whiting	33
Lithium Carb	27
TOAL	100
Soda Ash	30
Titanium dioxide	15

FIRING RAMP FROM JOHN POST’S EMAIL 10.10.2010
200 degrees an hour up to 2132
100 degrees an hour up to 2200
drop at full speed to 1800
150 degrees an hour down to 1300

The Strontium Opal Blue is a beautiful glaze -- delicate and quite glossy --  but must be put on thick due to its translucence.

37.8 Custer Feldspar	75.6 Custer Feldspar
24.9 silica	49.8 silica
22.8 borate,Gerstley	45.6 Gerstley Borate
11.2 calcium carbonate	22.4 calcium carbonate
3.1 strontium carbonate	6.2 strontium carbonate
3 rutile, 0.4 cobalt carbonate	6 rutile, 0.8 cobalt carbonate

The center piece was strontium opal blue over candy apple red.  Yeah. Yucky.  Still, it might be a good effect over a different color.

FLOATING BLUE OVER CONE 6 OHATA

DO NOT MAKE THE MISTAKE OF SLOW COOLING THIS GORGEOUS GLAZE!

Normally this is a killer combination

but in a slow cool, with a thick coat of Ohata and floating blue on the piece -- it just turns blackish brownish blue

The flash makes it look nicer than it really does.  It is basically an inky black with vague hints of some color that MIGHT be there in the glossy blackness. This piece was dipped first in Ohata cone 6 and then in floating blue.  I did quick dips because I did not want it to run under the handle like the last piece did.  I even washed off the glaze under the handle more to help it not run, but it ran and puddled on the cookie under it anyway.  Next time, I'm going to try BRUSHING on the Ohata and then dipping it in floating blue.  Hope it works. 

NOTE TO SELF: DON'T LEAVE KILN OPENED ON 200 PER HOUR RAMP.

Well, ok.


Here is the email I sent Jen at 10:13 last night once I got to thinking about a firing ramp that progressed at 200 an hour to 2100 degrees:


Dear Jen
I left the kiln lid open a bit. I was going to come in and shut it in the morning.  I hope that is ok.  I turned on the fan in the kiln room also.

It is held open with that little metal thing that is built into the kiln.

I hope I did not mess things up by doing that.  Sorry if it was the wrong decision to make.  Geez now I am worried.

much love
DJ




Heer is the email I got from Jen at 8 am -- but I had already left for the studio before I ever read it.


DJ - that is not good to do when the firing will be going up so fast.  Probably will be ok this time.  But if you haven't shut the lid by now (8am), go up there now.  It is hard on the kiln at higher temps.  When it is only a bisque firing the temp will be around 200-1000 degrees in 12 hours.  I figure yours will be around 2000 at this time.  Not good.
I'll be at Lee in about 30 min.
jen


so...um... don't do that any more, self.

10.12.2010 FIRING IN SMALL ELECTRIC KILN

I started the firing of several test glazes yesterday at 7:45 pm.  I left the kiln lid cracked open with the little latch built into the kiln.  It was around 285 degrees when I left last night at around 8:45.

The firing ramp is:
Ramp 1 -- 200 an hour to 2100 degrees
Ramp 2 100 an hour to 2232 degrees -- hold 8 minutes
Ramp 3 -- cool as quickly as possible to 1800 degrees
Ramp 4 -- 100 degrees an hour til it reaches 1300 degrees
END

However, by the time I get to the school this morning and close the kiln -- its gonna be close to 2100 degrees. Maybe it will just help the cooldown to 1800 go better......

I should have shut it last night when I left. I was not thinking how quickly it would reach temp.

GAAAAAAAAAAAAAAAAA!

KILN OPENING FOR HIGHFIRE GAS REDUCTION 10.11.2010

Lee College Ceramics, Baytown Texas
Prof. Jen Herzberg


DJ Brewer writes:
We had the best firing ever this time -- just awesome reduction.  The colors were spectacular -- we even good some good carbon trapping going on.  Phil's ash glazes were super.  I got an AWESOME piece with Hank Murrow's shino recipe that uses low melt spodumene and Helmer kaolin.  I'll add shots until they are all up.  Right now I'm putting up the ones of the Kiln Opening, front shelves and back shelves

Jen called me as soon as I arrived for the kiln opening to ask me about what glaze I used on a bowl that came out beautifully.

I told her it was Hank Murrow's shino. It flashed and blushed and carbon trapped -- it was amazing coloration from just one glaze

Amazing! I'm going to mix up some more of it.  I think I used the smooth shino recipe, but I'm going to mix up some of both of the recipes below for the next highfire.

Two of the ingredients are hard to find -- lowmelt spodumene and Helmer Kaolin.
You can get low melt spodumene (also called montebrasite ) from http://www.igctechnologies.com/
You can get Helmer kaolin from Wendt Pottery
http://www.wendtpottery.com/helmer2.htm

You can also use McNamee kaolin, but I did not get any of that.

Here is the recipe that Hank Murrow emailed me a long while back

Cryolite........................................ 0.6 %

Nepheline Syenite........................ 55.4

Low-Melt Spodumene................. 18.0

McNamee Kaolin........................ 26.0

100.0 %

Add: Veegum T.......................... 1.0 %

0.159 K2O 1.593 Al2O3 5.246 SiO2

0.534 Na2O 0.006 Fe2O3 0.023 TiO2

0.041 CaO 0.067 P2O5 0 . 0 0 0

MnO2

0.010 MgO 0.101 F

0.256 Li2O

White where thick; red where thin.

Best with early reduction firing with a long

concluding period of oxidation, or a soak

in oxidation during cooling. Yields a very

soft and fat surface with crawling. Crawls

more strongly if fired soon after glazing.

Note the low (3.3:1) silica to alumina

ratio. Cryolite seems to deepen the color.

Perhaps while outgassing, the fluorine content

carries iron from the clay to the glaze

surface. Low-melt spodumene contributes

phosphorus, which (as in Shaner’s Red)

also helps the fire color. McNamee kaolin

is a Georgia clay having a lovely blush of

color in the wood fire, probably because

of its iron/titanium content, which is also

beneficial in Shinos; Helmer kaolin can

be substituted.

Hank’s Smooth Shino Glaze

(Cone 10, reduction then oxidation)

Cryolite........................................ 0.8 %

Custer Feldspar............................ 32.2

Nepheline Syenite........................ 35.0

Low-Melt Spodumene................. 18.0

McNamee Kaolin........................ 13.0

Silica............................................ 1.0

100.0 %

Add: Veegum T.......................... 1.0 %

0.287 K2O 1.292 Al2O3 5.484 SiO2

0.428 Na2O 0.005 Fe2O3 0.011 TiO2

0.034 CaO 0.064 P2O5 0 . 0 0 0

MnO2

0.006 MgO 0.129 F

0.245 Li2O

A white satin where thick; red where thin.

Best with early reduction and a long,

concluding period of oxidation, or an

oxidation soak during cooling. Produces

iridescence with oxides.

I sent Hank the images and he said that he thought it was the Smooth shino recipe -- that's what I recall also.  He said he'd never seen it carbon trap -- but it did on a tiny teabowl I made in the spring.  I'll have to get a photo of that up also.

Phil's Woodash Menagerie!

Phil's got it down. He made glaze of 50 percent wood ash with cobalt in the blueish ones and copper in the green ones and the brown ones had no colorant added. The glazes don't dribble down on the kiln shelves any more.  He sprays 2 coats on the base, four on the middle, and 6 on the top.

Phil de man!


More goodies on the table

Pleased potters parlay over pieces.

Nice Teadust and bright copper reds

Lizard Brush Holder

Newborn Baby Cyclops covered in Monster Snot and drool

I'll post more later.....

It's been a long day.