The Official "Ask the Artisan" Community Topic

[JRS22]

I'm an amateur but I have 2 comments on your post. First of all, where I take classes cone 6 is considered high-fired and results in strong vessels, stoneware not earthenware. Second, at this studio the glazes are tested on the clays that are regularly available at that studio. Results are often unpredictable if the clay/glaze combo is not tested and people have suffered through some weird failures.

I'd love a recipe for a crawly shino glaze that works at cone 6 so I hope you get an answer to that question.

[JBaymore]

Not "crawlie".... but good for basic shino-ish look at cone 6 oxidation on a very dark stoneware body.......

35 Frit 3195
24 Silica
16.2 Cornwall Stone
7.8 Whiting
6 EPK
4.8 Zinc Oxide
6.6 Tin Oxide
2.0 Red Iron Oxide

Try subbing ball clay for the EPK and also increasing the content of that slightly to try to get the crawling.

Cone 6 reduction.........

Spodumene 22.8
Neph. Syenite 54.5
Ball Clay 14.9
Gerstley Borate 4.9
Soda Ash 2.9

Try upping the ball clay content slightly to see if you can get the crawl better. Up the soda ash for more carbon trapping (in "dirty" kiln firing).


BTW.... cone six is considered "mid-range".

best,

...................john

[GreenwoodStudio]

Very cool, Fivestar. First things first. Have you thrown on the wheel before? You may be putting the cart before the horse if not. Don't go into it with expectations of a finish product or you will almost certainly be disappointed and frustrated.

Let us know what level your at and I can offer some more specific advice.

[JRS22]

BTW.... cone six is considered "mid-range".

best,

...................john

In terms of strength of the pottery, impact on glaze, or both?

[FiveStar]

Thanks for the replies John and Shawn!

I actually have a bookmark on my computer for a "John Baymore Shino" recipe I liked a lot. Thanks for the recipes John.

And no, I have absolute zero experience on the wheel. I have high hopes, but don't expect to make anything too amazing. I'd be satisfied with one decent yunomi by the end of the 6 weeks class.

I'm mainly just putting a feeler out for glaze ideas. The woman running the class was telling me she liked to encourage beginners to view some of their early pieces as a great way to do some glaze testing

Thanks again!

[JBaymore]

BTW.... cone six is considered "mid-range".

best,

...................john

In terms of strength of the pottery, impact on glaze, or both?

It is just the standard term for that firing range.... cone 4 to 6.

Clay bodies don't happen to work out as a "linear progression" for strength qualities by the firing temperature.... although some folks will try to tell you that. Some cone 04 bodies are stronger than some cone 9 bodies, and every other combination you can think of. Ther are lots of measures of "strength" also...... impact resistance, tensile strength, compressive strength, lateral shear, and so on.

The higher one fires, the more silica (SiO2) there can be in a glaze formula. As a very general rule, the higher the silica content, the more durable the glass can be. Pure silica glass is very physically strong and chemically inert.......but it melts at such a high temperature that it is not useful for pottery. So we lower the melting point with fluxes. The higher the flux to silica ratio....the more compromise in the qualities of the glass produced. Some particular flux choices compromise the qualities more than others too. It is a complex science.

One firing range is not "better" than another, they are just all different.

best,

....................john

[JBaymore]

I actually have a bookmark on my computer for a "John Baymore Shino" recipe I liked a lot.

Likely that is my usual American Style Shino that I fire at anywhere from cone 10 to 14 (different effects) in a wood kiln in pretty heavy reduction. Won't do anything for ya' at cone 6 .

Glad you like it.

best,

..................john

[JRS22]

One firing range is not "better" than another, they are just all different.

best,

....................john

That's good to know as I have no choice of firing range unless I change schools, which I don't want to do.

Thanks for the detailed explanation.

[FiveStar]

Thanks for the detailed explanation on glazes and temps, John! That is the most concise description I've seen.

And yea, I bookmarked that glaze recipe when I thought we were going to be firing to cone 10. They have a gas kiln that they fire at cone 10, but it is only available to the resident potters.

I'm just excited to get my hands on some clay and see what comes of it. I need an outlet/hobby to occupy me, and I'm excited to explore making pots.

[JBaymore]

I need an outlet/hobby to occupy me, and I'm excited to explore making pots.

"Beware the Dark Side! That way lies obsession, cracked dry skin on the hands, and financial ruin."

best,

................john

[paul haigh]

Of course John nailed it (hi John).

If you're looking at making teaware- I would not be super concerned about strength right off the bat (a little pottery pun) with respect to glaze. That cracked glaze (crazing) that some people really like dramatically weakens a pot. Crawly glazes will likely effect strength.

I have pots with lots of local sand and rocks in them, with crazed woodfired glazes that I've used on a regular basis for years and throw in the dishwasher- and they keep on truckin. Of course they may eventually give up the ghost, but we all do eventually.

Focus on the basics- nice even thickness throughout, throw a lot of cylinders (the basis for all shapes) and you will have fun and function. Use some good proven glazes and experiment a bit later (IMO)- that's your best shot at a successful start and foundation.

Have fun, post your results, and keep at it!

[JBaymore]

I would not be super concerned about strength right off the bat (a little pottery pun) with respect to glaze.

Uhhhhhhhhhhhhhhhhhhh....................... groan.

Hi Paul.

best,

..................john

[biglou13]

Google cherry blossom shino, from clay arts. 4 ingredients. Beautiful shino ish. I'll try and post pics of my test with this glaze.

I'd stick with the house clays and house glazes at first. . And as boring as it sounds learning to pull Cylinder consistiently FIRST will so fast track your tea ware vs. trying to make a Chawan first day.

I'm pretty new to pottery and tea ware also. I'm in my 3 rd class and 100 pounds clay later..... I'm just now barely making passable Chawan, yumoi, gunomi.

Have you started your class yet? Definitely keep us updated.

[FiveStar]

Thanks for the advice biglou!

Haven't started yet, but the first class is next Mon. the 11th. I'm not even sure if I will get my hands muddy on the first day, but it is a 6 week class, with 6 hours of free studio time as well. So I hope to come away with SOMETHING. Even if it is a little simple cylidrical whiskey cup, I will be happy. I'm sure the "house" glazes and claybodies will be sufficient. I live in Asheville, NC home of Highwater Clays. They have some very popular clays, and some nice looking cone 6 reduction stuff.

Will let you all know how the first class goes.

[biglou13]

Cherry Blossom Shino

40.00 Nepheline Syenite
40.00 Spodumene
10.00 EPK Kaolin
10.00 Soda Ash

It's not really cherry since there is no color in this. And this version is for cone 6 or 7. My sample was fired to cone 6 electric, oxidation. And it's from ceramicmartsdaily. 33 tried and true glaze recipes. It doesn't crawl but is the closest to that softer shino in my tests.(pictures soon).

Not a lot of time in studio my class is 6 weeks with 2 weeks open time. And we can go work in studio any time it's open, and your not,interfering with other class. ( we're lucky ). There are a lot of great pottery resources in your area,including some great tea ware artisans. And wood fired kilns!!!!

If allowed I'd bring a ball o clay home and make a pinch/coil/slab/ carved ---- hand built piece (to feed the knead)

Ps. Your wife rocks, for,getting you class for a gift!!!!!

I could talk about tea ware for days. Unfortunately ,other than teacher, no one at studio understands tea..........