Thursday, October 14, 2010

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 6X1X2X3X5
Neph Sy18365490
Frit 313414284270
Whiting204060100
OM418365490
Silica306090150
total100200300500
oxides
Chrome Ox0.20.40.61
Tin Ox7.51522.537.5
Cobalt Carb1235
RIO0.511.52.5
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 6X1X2X3X5
Neph Sy18365490
Frit 313414284270
Whiting204060100
OM418365490
Silica306090150
total100200300500
oxides
Cobalt Carb1235
R I O0.511.52.5


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 313410.8
Neph Sy23.1
Bone Ash10
Magnesium Carb6.2
Whiting7.7
EPK21
FLINT21.2
TOTAL100
BENTONITE2
Red Iron Oxide12
Lithium Carb2

JEN'S JUICY FRUIT VARIATION FROM JOHN POST -

CONE 6X1X2X3X5
EPK30
Gerstley Borate27
Neph Sy147
Flint (Silica)36
Whiting33
Lithium Carb27
TOAL100
Soda Ash30
Titanium dioxide15

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. 

15 comments:

  1. DJ, thanks for sharing pictures and notes....looks like a lot of work and fun! Love the sunny yellow...reminds me of my grandma's kitchen....hope to stop by and see y'all one of these days with Chuck.....be blessed, Kersten

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  2. miss you Kersten. You make me wanna become a happy pagan!Think I'll go perform some magic in my studio today!

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  3. DJ - nice colors! The only thing is I don't think JJF on the mug is. Food safe due to excessive lithium. I'm Nancy but it won't let me comment other than via anonymous :(

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  4. Hi Nancy! I don't understand the comment thingie here, but at least it let you comment!

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  5. This comment has been removed by the author.

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  6. Nice firing! Nice photos!
    On that Raspberry Blue, let's try it again but on a clay body with iron.
    On that Praesydimoniumum Yellow...is that food safe?
    That Tomato Red and JuicyFruit variant...quite mesmerizing...especially for a mid-range electric firing! Most excellent!
    Your Ohata and Floating Blue combination...there is a combination calling my name. What was your firing schedule on it?
    Paula

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  7. Is this reduction or oxidation?

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    Replies
    1. Thank you! Just made this glaze in my ceramics class. I am excited to try it out!

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    2. Which glaze? Some of them require a slow cooling ramp. Let me know which glaze you made and I'll let you know the ramp.

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    3. Oh that one you can fire any way you want. It comes out a true purple for me. Hope you have good luck with it. I'm doing a multicolored piece and using that shade of purple on the piece. I'll post pics later once the firing is done.

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  8. Hi, I was wondering which glaze is on the upper part of the bowl in the tomatoe red 13 and Juicy Fruit varient. I assume you dipped the upper part in one glaze and then the lower half in the other glaze?
    arteacher1@yahoo.com

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  9. Hi there~ Laurie here, in 100 Mile House, B.C. I've made your Purple and it is truly purple. Thank you. However, it comes out matte for me. I fire to 2169* with a 25* offset and I come down at 150*/hr to 1800. I think the matte surface means that I am getting too much crystal development. What temp do you fire to for DJ's Purple?

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