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Ash Glaze

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Biglou (and all),

 

Good starting point.........

 

33.3 % washed or unwashed wood ash

33.3 % granite dust or any feldspar

33.3 % local red clay or redart

 

Center point of a triaxial blend. Works niceley about 95% of the time no matter the particular ingredients. Adjust slightly as needed.

 

best,

 

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

http://community.ceramicartsdaily.org/gallery/image/3876-ash-glaze-detail/

 

Results of above recipe

 

I used wood ash from BBQ restaurant

Lizella clay

Custer feldspar, and nepsy

 

Well turns out John b says it shouldn't work @ cone 6

 

Well it made a glaze..... It kinda just lays there , earthy brown sort of satin like finish part matte part shiny.

Some small black specks prolly from impurities in ash

It doesn't run. See finger mark from dipping lower left

Not what I was thinking as result but I thought it was some what a successful run.

It's a little too well behaved

I was expecting some misbehavin'

 

No leach tests run. Yet But no real " nasties" in this one.

 

I need to tweak it I think I'd like to see it a bit more glassy I think ill up the flux and see what happens and maybe some some colorants

 

thanks for the update- very interesting read! I have wood ash from some ash trees (chopped down due to the  boaring beetle) and some charcoal ash as well.  

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Biglou (and all),

 

Good starting point.........

 

33.3 % washed or unwashed wood ash

33.3 % granite dust or any feldspar

33.3 % local red clay or redart

 

Center point of a triaxial blend. Works niceley about 95% of the time no matter the particular ingredients. Adjust slightly as needed.

 

best,

 

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

http://community.ceramicartsdaily.org/gallery/image/3876-ash-glaze-detail/

 

Results of above recipe

 

I used wood ash from BBQ restaurant

Lizella clay

Custer feldspar, and nepsy

 

Well turns out John b says it shouldn't work @ cone 6

 

Well it made a glaze..... It kinda just lays there , earthy brown sort of satin like finish part matte part shiny.

Some small black specks prolly from impurities in ash

It doesn't run. See finger mark from dipping lower left

Not what I was thinking as result but I thought it was some what a successful run.

It's a little too well behaved

I was expecting some misbehavin'

 

No leach tests run. Yet But no real " nasties" in this one.

 

I need to tweak it I think I'd like to see it a bit more glassy I think ill up the flux and see what happens and maybe some some colorants

 

thanks for the update- very interesting read! I have wood ash from some ash trees (chopped down due to the  boaring beetle) and some charcoal ash as well.  

 

One other question… If I contact a granite counter top place to see if they have dust from cutting the counters do you think that would be the same thing as granite ash or is there a more pure form? 

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Wyndham    98

 

The easiest ash for me to obtain is from my BBQ, Kingford briquettes. It burns to a fine dust, I do put it thru a sieve to get it finer and mix it with water to spray it on my pots. I do not wash the ash. Check out my gallery to see my ash glazed pots.

Aloha, Ken

I thought briquettes had a small amount of cement in them. Did you have to adjust your glazes to take into account for the cement?

 

Jed

 

I heard somewhere that it's also a bit of clay or bentonite as a binder, I don't think it's enough to matter. Looks like a good reason for some BBQ, just to test, just to test :)

Wyndham

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JBaymore    1,432

You can use charcoal briquette ash for ash glazes... you just have to account for the silica and alumina that the inorganic parts of the bindwers introduce.  It's a little more "refractory" than most straight wood ashes.

 

best,

 

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

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JBaymore    1,432

Granite dust is granite dust. BUT.... be aware that some cutting operations use fine silicon carbide as a cutting medium... and that gets mixed into the granite dust. Changes everything. Plus some places cut all manner of stone stuff... and that also changes everything in the dust.

 

best,

 

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

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neilestrick    1,381

Back in my ash glaze days, I primarily used BBQ ash, which mostly came from briquettes. It was easy to get, as my friends and I all had grills and we used them all the time. It was not a fluxy as regular ash, because of the binders (as John said), but still worked very well. I was told the binders were usually clay, but from what I have found online binders can be starch, wax, bentonite-type clays, or just about anything else you can think of that's sticky. Combined with what I got out of fireplaces every spring, I had a really good supply year round.

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Biglou13    202

Take it to 9 Lou.  ;)

 

best,

 

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

will do.

 

can i change spar to nepsy and get similar effect as higher cone fire

 

or frit or talc for that matter

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neilestrick    1,381

Changing the spar to Neph Sy will help it melt lower, but probably not as much as is necessary. You may need to add some frit or Gillespie Borate to get it all the way down to 6. Might only need as little as 3%.

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neilestrick    1,381

How close is gerstley borate to Gillespie borate?

 

Gillespie Borate borate is a direct substitute for Gerstley, but it seems to be a bit stronger than Gerstley in the melt. I'm not sure which analysis of Gerstley they used for their formula. Gerstley is a conglomerate of minerals- Ulexite, Colemanite and Hectorite. These minerals occured in widely varying percentages, which accounted for the inconsistency in Gerstley. Gillespie uses the same 3 minerals, but blends then according to a specific formula so it's consistent from batch to batch.

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Dick White    155

Regarding the traditional inconsistency of Gerstley, I heard that when Laguna bought the mine and reopened it, they mined a bazillion tons of it, ground it, and put it all in a huge warehouse where they shoveled from end to end with dump loaders until it was all uniform. Thus, they now have many years supply of a consistent product. The analysis is slightly different (and published on their website) than before, but it is now a known quantity and reliable product. If anyone has heard differently, please advise.

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neilestrick    1,381

Regarding the traditional inconsistency of Gerstley, I heard that when Laguna bought the mine and reopened it, they mined a bazillion tons of it, ground it, and put it all in a huge warehouse where they shoveled from end to end with dump loaders until it was all uniform. Thus, they now have many years supply of a consistent product. The analysis is slightly different (and published on their website) than before, but it is now a known quantity and reliable product. If anyone has heard differently, please advise.

 

Yes, the current supply is supposed to be pretty consistent. We've had a lot of conversations here about Gerstley, some quite heated. I started using Gillespie when it came out and just kept with it.

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Biglou13    202

Added 3% GB

 

Can't tell from bad picture but it glassed up more , from matte ish finish.

There some more green in the throwing marks.

 

It's not the "ash glaze" look But still attractive and interesting glaze

 

Unfortunately can't do cone 9 tests.

 

I think I'll add some frit..... Next test

post-25544-0-27961600-1395923018_thumb.jpg

post-25544-0-27961600-1395923018_thumb.jpg

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jrgpots    231

Do you want some tumbleweed ash to try?

If so, just e mail me. Shipping would be $12.35...

 

I haven't finished my gas kiln conversion yet, so I haven't taken my test tiles to cone 10 yet. But they are quite white before they melt.

 

Jed

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Biglou13    202

I kinda like the the well behaved brown of the cone 6 ash glaze if Ill test leaching and crazing, but I may keep it. (But keep testing, need to feed the need to tinker) Ok I have to admit I'm partially biased 'cause I really want it work so I can say its made a reused local waste product...... And appeal to the greener side of potential buyers. (Not that I m making an effort to sell anything)

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