Saturday, November 20, 2010

Nov 19 Firing and Glaze Tests

Well!
I finally had some good results!

Lets get to it shall we?
This was a cone 10/11 reduction firing (maybe not reduced enough).
All ware was single fired white stoneware from Quyle Kilns. Glazes were primarily sprayed.
Kiln was held at 500 F for 1 hour and again at 1800 f for 1 hour. Reduction started at 1800 f, after the soak.
At 2200 f I added some wood for extra reduction, and then held the kiln in reduction at the top for about an hour. Cooled to 2000 f over about 1 hour and then shut off.

First the glaze tests, then the ware.
I decided to give examples of how I was taught to convert formulas to small batches.
Maybe some of my struggles lie there? I am NOT a math person...

Click on any image for a larger view, and, as always, comments and input are appreciated!


Tenmoku

From the Nov Ceramics Monthly.
Not sure what happened.
Not enough redux? Not enough Iron Oxide?
Maybe I put 10 grams of RIO instead of 100?

Whiting.....................20  (200 grams)
Custer.......................35  (350 grams)
Ball Clay...................15  (150 grams)
Silica.........................30  (300 grams)
Red Iron Oxide.........10  (100 grams)









From left to right:
1/2/3 dip || Rutile wash, over/under || Iron Ox wash over/under || Over Malcom's Shino || Over Shaner Yellow || Over Bone Ash White

Vanadium Green

From the book "The Practical Potter" by Josie Warshaw.
I didn't get the results I expected, but I'm really excited about a couple of these!
I may play with the colorant numbers a bit.

Neph Sy......................................................31  (310 grams)
Whiting........................................................31  (310 grams)
Fire Clay  (subbed with Hathorne Bond).......14  (140 grams)
China Clay...................................................12  (120 grams)
Copper Ox....................................................2  (20 grams)
Vanadium Pentoxide......................................8  (80 grams)









Left to Right:
1/2/3 dip || Rutile under/over || RIO under/over || over Malcom's Shino || over Shaner yellow || over Bone Ash White

Willie Helix

Again, not at all what I expected.
Some potential, but not what I'm looking for (what I'm looking for is something like the examples in John Brit's book).

Neph Sy ...............................42.9  (429 grams)
Whiting..................................20.4  (204 grams)
Silica.....................................24.5  (245 grams)
Kaolin...................................12.2  (122 grams)
Copper Carb...........................5     (50 grams)
Bentonite.................................2     (20 grams)










Left to Right:
1/2/3 dip || under/over Rutile || over/under RIO || over Malcom's Shino


Left to Right:
over Shaner Yellow || over Bone Ash White || over Matte Black || over Vanadium Green


Some Pots...



European Butter Dish



I got a request for a square, 2-stick style butter dish.
this was what I came up with, though its a little too small so I will have to make them about 10% larger next time. Also want to add some texture to the surface.

This would also make a great cheese plate I think.
I like this glaze combination too...




Little Yunomi


 Again working with Gary's Gold and Bone Ash White.
Playing with the rim a little.
I'm just happy with this little guy.
More exploring to do...





Some Bowls

Again, playing with altered rims.
This is simply Gary's Gold inside and out. Its a little too much of that glaze for me personally, though it is one of my tried-and-trues.
This bowl's bigger than it looks...maybe 4.5 cups volume.

Then there's this smaller tri-lobed bowl. My friend calls them Wave Bowls - nice.
This one has a Bone Ash White liner.
Its about cereal bowl sized...2.5 cups?
I'm really liking the over spray of the gold onto the white inside this.
Need to play with overlapping glazes in the spray booth!

I have a request for a set of these.
I'd like to do something nicer with the glaze.
Maybe I'm just bored with the gold...






Mugs!


Yep!
Wanted to make some mugs for some of my favorite guys.
These are Bone Ash White. The inside is just that.
The outside is over a Rutile wash.
These were really fun to make and I'll definitely be making more and playing with glaze combinations on them.
These 3 are personalized with the guys' initials on the handles.
They're nice and big, and I like a generous handle that you can get a really good grip on.

I need to make a larger, tankard-style one for beer,
After all, one can only drink so much coffee right?

Well, that's about it.
I had a couple of kitty saucers in the kiln too, but there's not at all exciting, so I didn't include them here.
That's pretty much a full kiln load for me.
I dream of a larger kiln, but for now, this will do.

CMCK

Tuesday, November 9, 2010

Electric to Propane/Wood Kiln Idea

I'd appreciate any input from the experts on my idea here.
I recently picked up an old Skut 3-ring electric (non working and I'm not into electric firing).
Its the same size and configuration as my current high fire converted kiln, but in better condition, so I'm going to switch them out.

That leaves me with an extra kiln to play with and this is what I'm thinking.
I toyed with the idea of soda, but have decided instead to play with woodfiring.
I LOVE the results, and thought this might be manageable.
Don't know any more about woodfiring than I do about soda (nothing), but I figure a kiln is the logical place to start.

Sunday, October 24, 2010

Oct 24 Firing

Well...
No test tiles in this firing.
I stuck to 4 glazes - the matte black from From the March/April 2010 issue of PMI , Melinda's Not Yellow , Shaner Yellow , and Lasse Ostman's Green Crackle.
I used 2 clay bodies, both from Quyle Kilns. The iron rich Sandstone Buff and the Silverstone white body.
Single-fired all, and I can see I need to work on my glaze (spraying) application. A bit thin I think.


This was a straight oxidation firing to cone 10/11, though I did try to get some reduction on the bottom shelf by using shelf posts to create a sort of saggar around the pieces on that shelf. Not terribly successful though.


Click on any image to see it enlarged.
Please to enjoy and comment as you see fit.



Beer Mug.
A beer mug for Craig.
I don't like the lip on the mug - not sure why I made it so flared.
The liner glaze is a nice bone ash white, the outer one is supposed to be a flat black. Not sure why its so shiny.
The biggest issues are the lip of the mug and that I didn't get the glaze thick enough - especially on the handle.

I'll try again...





Child's Cup and Bowl
A cup and bowl I made for my new, 2yo granddaughter Alivia.


I am not really kid-friendly, but I really wanted to do something for my new granddaughter and new daughter-in-law.


I initially thought about a 2-handled cup, but got some really great ideas from everyone on ClayArt and was inspired.

I hope she likes them...



Shaner Yellow inside and out, with irin oxide wash.

Iron rich "Sandstone Buff" clay body by Quyle Kilns.

BTW...
I did some experimenting with resists and found the best one for things like impressed letters is Shellac! 




Jar


A Jar for Susan's birthday.



Liner is Bone Ash White, outer glaze is Shaner Yellow over a rutile wash. 

On Quyle's "Silverstone" white clay body.












Jar
Another jar...

I go back-and-forth on this one.
I like the form. I need to work on that knob a little though.
Do I like what the glaze is doing or not?
I expected it to do something else. Not be so runny. Not pool so much. 

But then I look again and those pools and breaks and layers of glaze keep 
my eye coming back for more, so...

Lasse Ostman's Green Crackle with Shaner Yellow liner. On Quyle's "Silverstone".








Jar
Another jar with Lasse Ostman's Green Crackle.
On the top shelf of the kiln, and a totally different result.
Same clay body.
The glaze coverage of both the Shaner Yellow liner and the outer glaze are not good, so I may re-glaze this one.
I do like the form.



Someday Jars

My son and his new family are going to have a tough time in this economy.

I wanted to make something to both welcome his wife into our family and to help them save a little.

This is a stopperless bank.
A thrown and altered bowl with additions.

Melinda's Not Yellow glaze over an iron ox wash, on iron-rich "Sandstone Buff".
I tried to create a sort of saggar to encourage some reduction by enclosing these pieces with shelf posts. Not sure how successful it was, but I'm pleased with them.




Some Uglies
Well, ye never know unless ya try right?
I'm just beginning to play with mugs and handles and whatnot.
I still feel glazing is my big weakness.

Some days I just want to toss it in, buy pre-mixed cone 6 glazes and an electric kiln and be done with it.
But I think there's something out there in High Fire Land calling to me.
And when I see what can be done, I want to go to there.


Lastly, the Raku Boxers

I am very involved with dogs - specifically the Boxer breed. More specifically, Boxer Rescue. I did hands-on rescue for 15+ years. Part of that time was spend in Missouri working largely with puppy mill throw-aways.
I can't rescue anymore, but I do try to keep my hand in, and one of the things I do is fundraising.

My friend in Nottingham, England owns a bisque pottery.
One day she surprised me with a charming little slipcast boxer figurine.
That got the ball rolling...
Now, she sends me a box of bisqued boxers from time-to-time and I raku them. Its terribly fun, and helps rescue. If there's a particular rescue needing funds, I can put one of these critters up on eBay and usually raise a hundred dollars or so for the rescue. 
Beyond that, I donate $10 to a specific national rescue fund every time I sell one.

Makes me feel like I'm still helping out ;-)



Wednesday, September 1, 2010

Latest Firing Results

Ok then...
My second load of ware that was glazed with the spraying technique, and I can see I need to learn to better judge my glaze thickness.
I also need to develop some reliable method for a slow cooling of the kiln to encourage crystals in my Tea Dust.
Click to Enlarge
This was a cone 11 reduction firing, though for some reason I didn't get as much reduction as I typically do.
Everything was raw glazed and single-fired.
Kiln was soaked at about 1800 degrees, and then light reduction was started.
Occasionally I added a couple of sticks of wood with an idea of increasing redux and adding some fly ash, but it smoked so much that I realized I had better wait till I could contact the local fire dept first to let them know I was not torching the Mother Lode to the ground.

Everything but a few test tiles was Quyle Kilns Sandstone Buff - an irn rich clay that is typically nice and dark in redux.




Click to Enlarge

Malcolm's Shino


Neph Sy.................40.9
Kona........................9.8
Kaolin.....................18.2
Ball Clay.................13.8
Redart.......................6
Soda Ash................17.3

From John Britt's "Complete Guide to High Fire Glazes"
Dipped 2/3 on damp clay. Tested on 2 dark and 2 light tiles, with the last tile having both Red IO and Rutile washed over and under the glaze. On one each of the light and dark tiles, I sprinkled a little coarse salt, thinking it might create some variation in surface moisture/soda ash migration (if I understand the theory behind carbon trap shinos...)
I guess I expected something more spectacular.
Anyone have any thoughts?



Click to Enlarge

Penn State Shino


Neph Sy .......................14.6
Kona..............................34
Spodumene.....................29
Kolin................................9.7
Ball Clay...........................4.9
Soda Ash.........................7.8


From John Britt's "Complete Guide to High Fire Glazes"
Dipped 2/3 on damp clay. Tested on 2 dark and 2 light tiles, with the last tile having both Red IO and Rutile washed over and under the glaze. On one each of the light and dark tiles, I sprinkled a little coarse salt, thinking it might create some variation in surface moisture/soda ash migration (if I understand the theory behind carbon trap shinos...)
Again, I guess I expected something more spectacular.


Click to Enlarge

Matte Black

Don't laugh...I forgot to add the colorants!

Cornwall Stone.....................42
Dolomite...............................15
Whiting.................................10
EPK.....................................23
Silica....................................10
    (forgot) Yellow Ochre........6
    (forgot) Cobalt Carb..........2
    (forgot) Chrome Ox...........1

From the March/April 2010 issue of PMI .
Dipped 2/3. Tested on 2 dark and 2 light tiles, with the last tile having both Red IO and Rutile washed over and under the glaze.
Now, Ms Bohls explains that she fires cone 10 electric, but I couldn't see any reason this glaze wouldn't work in my kiln. I did put the pieces on the top shelf, which typically gets very little reduction (its right under the flue.). Wonder why its not at least matte...



Click to Enlarge

Malcolm's Shino under...

Left to right:
Click to Enlarge
Shaner Yellow
Matte Black
Melinda's Not Yellow




Another tile with the Shaner Yellow over the Malcolm's Shino.
I am really liking this!
Definitely want to use this combo!










Click to Enlarge

A Couple "Matte Black" Items

Click to Enlarge
OK, I was expecting this butter dish to be Matte Black.
I still like it! It has a Rutile wash under it and has some nice interest.
Not as dramatic as I had hoped, but in looking at it, I wonder if it really would have been as successful if it was black.

On the other hand, I think this spice shaker would definitely have been more successful and dramatic in the black.
I think I will re-glaze this piece...its just not doing anything for me as is.






Click to Enlarge

A Few "Melinda's Not Yellow" Items

Well, I just love this glaze, and am so grateful to my Stay-at-Home mug exchange partner Melinda Collins for sharing it with me!

Click to Enlarge
A couple of spice shakers. The one of the left has an RIO wash under the glaze.

Wren House - I'm just starting to develop this. Put my own stamp on it.
2 things...
I found I have a weak spot on the neck when I alter the lip, but sticking a wad of clay there and stamping in my chock seems to solve that issue.

That blue streak is a piece of copper tape I got at the hardware store. Thought it would be fun to play with. Might do better over the glaze rather than under it.







Click to Enlarge

A Few "Coleman Tea Dust" Items


I did not spray this glaze thickly enough, and I'm having some issues cooling my kiln down slowly enough, but overall, its a nice glaze on just about anything.

Salt and Pepper shakers - what's to say?
Click to Enlarge
Another Wren House.
I think they should be a little larger, and I had some issues with correcting for torque. The houses were pretty wet when I cut the keyhole in the back for hanging. As they dried, the keyhole moved so now they will hang kinda wonky.

Click to Enlarge
Butter Dish...
The glaze was fine on this one, but its pretty warped. Not funky/good warped, but poorly executed warped.
I had a sushi tray in this load that looks like a record left in the sun too!
I need to make the slabs for these butter dishes thicker, and handle them less. Rutile wash under this BTW.

This was kinda interesting.
Click to Enlarge
That's a piece of that copper tape, cut into a pattern and applied to the tile before glazing. This pic is a bit over-corrected, and I don't think the results were all that attractive - a dark indigo matte area), but it was interesting to see what happened.

That's pretty much it.
As usual, I welcome input, critique, suggestion and comment. I always learn so much from you all.
Thanks for having a look!
CMCK

Wednesday, August 11, 2010

July 10 Firing

With a bit more care, some great advice and a change in glazing method, I'm pretty happy with yesterday's glaze firing.

I think its helping me to fill in the dead spaces around my ware with kiln posts to create and hold more heat and I think it maybe creates little micro-atmospheres in the kiln in reduction.
So that's what I've taken to doing.

Ron Roy gave me some valuable insight into crawling, and I took it to heart, doing a more thorough soaking at about 1800f to burn out impurities in the clay - especially important since I'm single-firing.

Lastly, I cleaned up an old sprayer and had a go at spraying glazes.
Besides the obvious benefits of even coverage and blending, I can see right away that its a great way to glaze greenware. Much less stress to the delicate pots!
So I bought a gravity feed sprayer from Harbor Freight and will be constructing a spray booth from a RubberMaid garbage can today.
With these minor breakthroughs, maybe I'll even learn to love glazing...

Note:
Cone 10 redux - single fire.
Soaked @ 500f for 1 hour, again at 1800f for an hour (per Ron Roy's suggestion) and held at the top, in heavy reduction for 45 minutes.


Moon Plate


So...
this plate is about 12" on a side.
Slabbed plate with thrown foot.
Its a white body, into which I squished bits of scrap from a dark body (probably trimming leavings from a bowl or something) which explains the halos on the plate's surface - the glaze (Lasse Ostman's Green Crackle) looks very different on a dark body than on a light one, and different again in reduction.





The glaze was sprayed on!
That's something I'm experimenting with and so far I LOVE the results!










Chachke Holders


Little Chachke Holders.
Just playing around - these would make good little test tiles. They're about 2: on a side.
Stronthium Blue glaze, dipped.













Noodle Bowl


I made this for an Empty Bowls event happening in my community.

Glaze (Melinda's "Not Yellow") is sprayed on, though not thickly enough, so I need to re-glaze I think.

Dark body with white slip inside. Same glaze over the entire piece. The textured band has an iron oxide wash.

I like it, but it needs better glaze coverage. 
Something to learn about spraying...


Butter Tray


My little butter tray.
Well, this was sure fun to make!
I really like how it turned out, with one minor flaw...its not supposed to sag like this LOL!

This is a white body.
Iron oxide washed on and removed and then sprayed with Lasse Ostman's Green Crackle.
Fired on the top shelf, so less reduction that the other pieces.





Hors Devours Plates


Each is about 4: on a side.
I know they were utterly flat when I put them in the kiln, but each has warped slightly.
Anyone have any thoughts on that?
The glaze is Melinda's "Not Yellow" and though I'm getting different results than she, I just love this glaze!
Here its brushed onto the dark body fairly thickly.





So, you all know the drill... feedback's happily accepted - constructive critique is even better!
Thanks for looking...
CMCK

Friday, August 6, 2010

16 Glazes, 80 Test Tiles!

Glazing is truly my weak point at this time.
I have a terrible time getting predictable results of late.
So I bit the bullet and did a whole lot of testing, with a mixed bag of results.
Please to enjoy...




Notes:
This was a cone 10/11 reduction firing.
My kiln is a small (3.5 cubic feet) electric, converted to a propane updraft. I did some experimenting with the load as well as the glazes...

On the bottom shelf, I posted around the edge of the round shelf, using 8 posts.
On the middle shelf, I places posts on their sides, 2 rows tall, creating a sort of saggar around the tiles, with just enough opening in the "enclosure" for the cone pack
The topmost shelf was covered with a shelf posted with just 4 posts, and then a baffle shelf was placed on that about 3" under the flue opening.

This was a single-fire load, on bone dry greenware -  I used 2 clay bodies - a high iron, groggy clay (Sandstone Buff from Quyle Kilns) and a white/gray body (SilverStone, also from Quyle).

For each glaze, 5 tiles were used - 2 of the dark body and 2 of the light body were dipped either 1/2 or 2/3, with 1 tile of each body being placed on the middle and top shelves.
A 5th tile of the combined bodies was glazed, with washes of red iron oxide and rutile brushed on both under and over the glaze. All the washed tiles were placed on the lowermost shelf.

The "saggared" shelf (the middle shelf) had much more reduction, which is noticeable in the bare clay at the bottom of each tile.
The tiles are numbered:
1= dark body on middle shelf. 2= light body on middle shelf. 3= dark body on top shelf. 4= light body on top shelf. 5 mixed body with RIO and Rutile washed over and under, on bottom shelf.
Click on images to enlarge.
whew!



Shaner Yellow


  • Custer...............29
  • Whiting.............20
  • Talc.....................4
  • Bone Ash............4
  • Zircopax............23
  • Red iron oxide.....4


Notes:
These were all dipped 1/2.
Has significant crawling on the dark body, but none on the light body.
Wonder why...





Melinda's Not Yellow

  • Neph Sye..........58.1
  • Dolomite...........19.3
  • Ball Clay.............3.9
  • Bentonite.............7.3
  • Zircopax............11.4
  • Tin Oxide..........2.1
  • Red iron oxide...0.5
Notes:
These were all dipped 1/2.
Melinda gets lovely blues and creams, breaking to rust.
She says this glaze is best with an RIO wash underneath, and better on bisqued  clay.
I didn't have any Tin Oxide, so I subbed more Zircopax.


Candace Black

  • F-4 Feldspar..........65
  • Whiting.....................5
  • Silica......................20
  • Kaolin......................5
  • Red iron oxide..........8
  • Colbalt carbonate.....5
Notes:
Just fail.
From "Complete Guide to High-Fire Glazes", by John Britt. All dipped 1/2.
First (and perhaps most importantly), I didn't have F-4 feldspar, so I used Custer.
Still searching for a nice black...


Snow White


  • Hawthorne Bond.....30
  • Custer.....................10
  • Silica.......................30
  • Oak woodash.........25
  • Zircopax...................6
Notes:
All were dipped 1/2.
Formulated playing around on GlazeSimulator.com .

Just not very pretty.
The glaze called for Tin oxide, so I added Zircopax at twice the amount. Again, crawling on the dark body, but not on the light. The dark body has much more tooth. 


Orange Peel


  • KMS Kaolin.....20
  • Custer.....31
  • Talc.....34
  • Silica.....15
  • Copper carbonate.....0.05
  • Copper oxide.....0.05
Notes:
Dipped 1/2. Again, playing with GlazeSimulator.com . This one has potential I think. Its satiny and touchable. I like what its doing over the Rutile wash. I think I might either sub Rutile for the coppers or just add it in. Might also try an addition/substitution of Chromium oxide.


Coleman Tea Dust

  • Custer.................40
  • Silica...................25
  • Whiting................16
  • Talc.......................7
  • Red iron oxide.....10
Notes:
Dipped 1/2, should have defloculated a bit and dipped 2/3 I think.
First, I didn't do a slow cool-down in this firing, so I didn't get any crystallization, but I knew that would be the case.
I really like how it reacts both over and under the Rutile.
Its a keeper...


No-Barium Blue

  • Strontium................31.9
  • Neph sye................53.1
  • Ball clay....................6.7
  • Silica.........................8.3
  • Copper carbonate.....4.0
  • Bentonite...................1
  • Zircopax..................10
Notes
1/2 dipped. From the article "Leaving Bariumville" on CeramicsArtsDaily.org .

The original recipe looked lovely on porcelain, but not so good on my clays. I didn't like the translucent quality, so I added the Zircopax for opacity. I like it much better now, and actually prefer it on the dark body.

Don't think it works with any of the washes.


Bone Ash white

  • NC-4 Feldspar.....40
  • Kaolin.....25
  • Dolomite.....30
  • Bone Ash.....5
  • Bentonite.....3 
Notes:
From the book "Complete Guide to High-Fire Glazes" by John Britt.

#1 & #2 - single dipped. #3 & #4 twice dipped. #5 single dipped.

I didn't have NC-4 Feldspar, so used Custer. I really like this on tile #4, though it crazed a fair amount.


Haynes White

  • Neph Sye.....45
  • Silica.....30
  • Whiting.....8
  • Dolomite.....10
  • Talc.....7
  • Bentonite.....1
Notes:
Dipped once, glaze was a cream consistency. From the book "Complete Guide to High-Fire Glazes" by John Britt.

Well...Its essentially a clear glaze.
It has something of a chun quality to it, and as you can see, is very different in heavier reduction.
Anxious to see it in an Oxidation firing.
I really like the life it has both over and under RIO,


Ostman's green Crackle


  • Neph sye...............55
  • Dolomite................23
  • China clay..............21
  • Silica........................1.25
  • Copper carbonate....0.75
Notes:
Dipped 2/3. From Lasse Ostman's glaze page.

When Mr Ostman uses this glaze, thinly, on a white body, in oxidation, he gets a lovely matte green crackle,

I wish you could feel this glaze and see it in person. Its so alive...I love ll its incarnations.
You can't tell here, but that red on tile #5  is crystal formation - perhaps encouraged by the RIO wash...


Gary's Gold


  • Dolomite.............21.02
  • Whiting...............10.51
  • Custer.................36.84
  • Silica...................31.63
  • Bentonite...............5.3
  • Ritile....................10.51
  • Red iron oxide.....10
Notes:
Dipped 1/2. From Gary Kelsey, Trenton, Mo.

One of my favorite, most consistent glazes. I just love it. More crystals on an iron rich body, but nice either way. Not really effected by either of the washes, but a dip of Celedon over it produces great effects.


Ohata Red



Notes:
Dipped 1/2 - best with 1 thin dip.
Shoot! Can't find my recipe right now.
I don't really like this glaze on its own, but under ash glazes it does crazy-wonderful oil-spotty type things.
tile #5 is showing over and under Rutile.










3/3/3 chrome Ash


  • Redart.....33.3
  • Silica...33.3
  • Wood ash...33.3
  • Chromium oxide...4
  • Bentonite....1
Notes:
1/2 dip. I was just playing around...so while I'm sure others have made this same glaze, its just out of my head.

I've mixed it up with Rutile, Copper oxide and with no oxides. I like it because it doesn't run, and has a lot of life to it.
I don't use it inside functional ware.
Tile #5 shows it under Rutile.


333 Chrome Ash Over Rutile


Notes
Half of each tile (vertically) is washed
 inside and out with Rutile. 
You can see the difference I think.

I find the more texture a piece has, the more interesting it is.












Well, that's all I have.
I always get such good feedback from fellow potters when I post here, and I'm pretty anxious to hear everyone's thoughts.

I'll be doing another test next week  same process, but in an oxidation atmosphere.
Looking forward to that!
thanks for taking a look!
CMCK