D. Michael Coffee (shyrabbit) Ceramics in Pagosa Springs, CO

[shyrabbit]

Re: D. Michael Coffee (shyrabbit) Ceramics in Pagosa Springs, CO

by shyrabbit » Aug 20th, '09, 17:46

C,
I think coloradopu was asking the question about the celadon firing.
Michael

[bonjiri]

Re: Fish Scale Glazes

by bonjiri » Aug 22nd, '09, 17:01

c,

Sorry for the slow response both here and to your PM's. I've had computer and wifi problems on and off for the last week...

I have two recipes for what is knows as "Fish Scale" glazes, I've been meaning to try for some time now. Generally, Fish Scale glazes tend to be very high feldspathic glazes that craze and that are applied rather thick. They look best over darker clay bodies.

You might also try the following recipes with various oxides to create different color effects. These recipes will produce milky white glazes with smooth "fat" and "buttery" surfaces. The excessive crazing will also likely give a visual depth to these glazes.

Maybe we can both, or any of the other potters here for that matter, test and compare our results here(?).

Michael

Glaze #1
cone 10-11, reduction

Soda Feldspar 80
Whiting 10
Clay 10 (try om-4 or EPK = different results)
Bone Ash 2

Glaze #2
cone 10-11, reduction

Cornwall Stone 85
Whiting 15

michael

GLAZE #1
Soda Feldspar 80
Limestone 10
OM4 10
Bone Ash 2
RIO 0.50

someone put a partial bag of limestone in the whiting container. glad the bag was still intact and whole.

so the recipe serendipitously was changed and it came out...

Glaze #2 also was limestone instead of whiting. now i have to try the whiting recipe.

[shyrabbit]

Re: D. Michael Coffee (shyrabbit) Ceramics in Pagosa Springs, CO

by shyrabbit » Aug 22nd, '09, 17:53

Cory,
Not to worry...as glaze ingredients are often referred to by different names for the same thing...

Limestone is whiting and they are both Calcium Carbonate, or another way to look at it is:
Limestone = Calcium Carbonate = Whiting

All names for the same thing.

The same thing goes for:
Silica = Quartz = Flint

Also, Limestone's chemical composition will change from mine to mine, this is generally true for most of the ingredients we potters use in our glazes. This is one of the reasons why the same glaze mixed in different areas of the country will often be quite different when fired.

I love working with glazes and all their nuances,

Hope this helps,
Michael

[bonjiri]

Re: D. Michael Coffee (shyrabbit) Ceramics in Pagosa Springs, CO

by bonjiri » Aug 24th, '09, 00:38

michael

mahalo. thanks for patience

i usually go by the recipe, percentages and don't use any subsitutions.

thank you for the information

thank you humbly
cory

[shyrabbit]

Re: D. Michael Coffee (shyrabbit) Ceramics in Pagosa Springs, CO

by shyrabbit » Aug 27th, '09, 16:27

Glaze firing today...the image below is of the reduction flame at the flue with the kiln temp @ 2050 F on its way to 2345 F

I posted this image just for fun...
Michael

[chicagopotter]

Re: D. Michael Coffee (shyrabbit) Ceramics in Pagosa Springs, CO

by chicagopotter » Aug 27th, '09, 17:31

Michael,

You firing an updraft? Think I might get into the fish scale experiment too. Probably run both thru regular cone 10 and a soda firing.

Thanks -- Chris

[shyrabbit]

Re: D. Michael Coffee (shyrabbit) Ceramics in Pagosa Springs, CO

by shyrabbit » Aug 27th, '09, 17:55

Chris-
Yes, I love my up-draft kiln. I posted images of my kilns back on my page 4, about half way down, if you're interested.

I've not had time to test the fish scale glaze yet. Just remember that it has to be applied rather thick or it won't render the scale effect. Did you see Cory's plate that he stained with RIO. Turned out nice I think.

I will be interested to see what effect the soda has on this glaze, might be a surprise(?)

I look forward to seeing your glaze tests.

Michael

[bonjiri]

Re: D. Michael Coffee (shyrabbit) Ceramics in Pagosa Springs, CO

by bonjiri » Aug 28th, '09, 03:08

Glaze firing today...the image below is of the reduction flame at the flue with the kiln temp @ 2050 F on its way to 2345 F

I posted this image just for fun...
Michael

cool

when do you start your reduction ?

cool photo !

[shyrabbit]

Re: D. Michael Coffee (shyrabbit) Ceramics in Pagosa Springs, CO

by shyrabbit » Aug 28th, '09, 10:40

c,

I start my reduction rather early @ 1560 F. Good for my shinos and for carbon trapping.

I would be curious what others do....?

Michael

[bonjiri]

Re: D. Michael Coffee (shyrabbit) Ceramics in Pagosa Springs, CO

by bonjiri » Aug 28th, '09, 13:32

c,

I start my reduction rather early @ 1560 F. Good for my shinos and for carbon trapping.

I would be curious what others do....?

Michael

michael

me too.
good for copper reds too

cheers

i keep it in this reduction with temperature rising until cone 10 goes over.

[chicagopotter]

Re: D. Michael Coffee (shyrabbit) Ceramics in Pagosa Springs, CO

by chicagopotter » Aug 28th, '09, 16:25

I usually start reduction around 010, maybe I'll try lowering the start temp with the next firing to see what happens

[bonjiri]

Re: D. Michael Coffee (shyrabbit) Ceramics in Pagosa Springs, CO

by bonjiri » Aug 29th, '09, 12:33

michael

how many days do you wait until you open your kiln ?

thanks

cory

[shyrabbit]

Re: D. Michael Coffee (shyrabbit) Ceramics in Pagosa Springs, CO

by shyrabbit » Aug 29th, '09, 12:52

michael

how many days do you wait until you open your kiln ?

thanks

cory

c,

I open the kiln the next day.

By the next morning the temp. has dropped to 650 F, at which point I pull the peep pugs and let the temp. drop to 425 F. I then open the damper an inch or so until the temp. drops to 250 F, at this point I start unloading. I'm usually unloading by noon.

Michael

[bonjiri]

Re: D. Michael Coffee (shyrabbit) Ceramics in Pagosa Springs, CO

by bonjiri » Aug 29th, '09, 22:42

michael

how many days do you wait until you open your kiln ?

thanks

cory

c,

I open the kiln the next day.

By the next morning the temp. has dropped to 650 F, at which point I pull the peep pugs and let the temp. drop to 425 F. I then open the damper an inch or so until the temp. drops to 250 F, at this point I start unloading. I'm usually unloading by noon.

Michael

michael

thanks !

wow. that is cool

can't wait to see some new pieces you have.

kiln openings are so exciting !

ALOHA
c

[Seeker]

Re: D. Michael Coffee (shyrabbit) Ceramics in Pagosa Springs, CO

by Seeker » Aug 30th, '09, 01:26

+1, me too!

Maybe something, mmm, red?