Tuesday, 10 March 2009

Wood Ash - Glaze Recipe Required

Following the demise of the 43 Horse Chestnut trees on the Barrington Court estate
I felt it would only be right and proper to try and make some Ash Glazes
from the piles of Ash now cooling down.
The trouble is as far as I am aware all the Ash Glaze recipe's I know are for Stoneware Glazes.
This is where you come in my fellow Potters.
Now is the time to scramble for your old recipe books if any one has a recipe
for an Ash glaze that fires to 1100 oc, I would love to give it a go.
If not I may be in the possession of a very large quantity of Horse Chestnut Ash.


potterboy said...

According to Tichane, HC ash contains 25.7% potash, 43% calcium oxide (lime), 4.9% magnesium oxide, 19.2% phosphate, 2.6% silica and 6.1% chloride.

He then talks about low fired - about 1200 or even down further - by using 20-25% ash to some frit - using number 25 frit he got a celedon like runny matte ash glaze that was very temperature sensitive. Most glazes seemed to be white, matte, possibly bubbly.

His final recommendation is to just try it - but doesn't sound too successful.

ang said...

mines really simple 90 gerstley borate and 10 ash (plus 2-5% copper ox for colour) which is usually red gum, for 1200-1220C i'd try a high alkaline frit 4110 or 4124 perhaps, are our numbers i'm sure yours would be diff..and play with the percentages...greg daly's book glazes and glaze technology is excellent and has pictures too..

potterboy said...

Flicking through Rogers, one potter in there is Lis Ehrenreich who has glazes that mature at 1180 using borax. Google her and if you like I'll send you the recipes - they are reduction fired though - and the recipes are in an odd format - not sure what they are (it doesn't say... typical.)

ang said...

oops knew i should have checked my journal....90 ash 10 gerstley borate 2% copper ox...what an irriot....!!!
i'll post my journal page so you can see the results,,

brandon phillips said...

i don't know of anyone off the top of my head that does work with ash at that low temp. you may be the first! ash is naturally a cone9-11 glaze so you'll have to put a lot of stuff in it to bring it down. frits being the main ingredient to lower it. my knowledge of frits is minimal at best and i think you guys may have different frits over there than we do. ang mentioned gerstley, throw some of that in as well. you'll have to have some clay to keep it in suspension, maybe 10% ball clay and throw in a little feldspar. you could try taking glazes you already use and subs. ash for something. the problem i think you'll face is crazing and how to eliminate it as ash isn't the most stable ingredient. good luck!

Hannah said...

frits fits and more frits. thats all i know. will keep my eyes open though

paul jessop said...

Thanks for the Input greatfully recieved.
Testing, Testing, Testing.

Tolulope said...

Pls i need updates on your research,
i am masters student whoiworking on low temperature ash glaze.
pls you can sendme the recipes.
i willbe grateful.
cosi really dont know where to start from.

Tolulope said...

my e mail

Michele said...

Did you have any luck Paul with the low temp ash glazes? I'm hoping to do similar, would love any advice / recipes you found that seemed to work!

janie said...

You might try this. Fires at ^6.

Wood ash 50.0
wollastonite 12.5
Ball clay 12.5
Kona F4 Feldspar 12.5
Gerstley borate 12.5


Not my recipe, although I have seen results of it. Beautiful!

Best of luck, and I would love to see your results.

Nancy Ortiz said...

frits fits and more frits. thats all i know. will keep my eyes open though

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