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BetsyLu

Ash Glaze Questions

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Hello, newbie here. I want to do some experimenting with making my own wood ash glazes from local woods. I've done a fair amount of research on the subject, but I do have some questions. 

 

1. I've decided to keep my variables simple in the first round of tests. I was thinking I'd do a simple recipe for ash glaze, which is 50 parts dry ash and 50 parts clay body. Does this sound like a reasonable place to start, or am I missing anything important? 

 

2. I have also decided to wash all of the ash I use. I like that it will be more stable/last longer in a mixed glaze and will be less caustic. I also don't want a SUPER runny glaze, and I read that there are more fluxes in unwashed ash. I am wondering, though, what is the best way to dispose of the lye-water that I will make through the washing process? I don't want to pour it into our septic system or kill any plants or hurt the environment. 

 

3. I'll be making plates mostly, maybe some shallow bowls. I was thinking simple, flat test tiles would be the best way to test colors and would be easiest to display later. I am a little worried about super runny glazes, though. Any suggestions for a good test tile to test glazes used on plates? 

 

4. I am not sure what the best glaze application process would be. I don't have access to a sprayer, and it will be difficult to dip plates (especially if I don't have a LOT of glaze mixed up at a time.) Any ideas how to use either a sponge or a brush to get a fairly even coat? (I'm okay with some variation in pattern, but I want to make sure the whole surface is glossy and glazed) How thick should my glaze be when I paint it on? (Should it cover my hand completely and be like runny yogurt or should it be thinner?) 

 

5. I've read that it's important to gather pure ash, and that ash from the fireplace doesn't always work because of the newspapers/magazines used in starting the fire. How important is it that the ash I use for glaze is absolutely 100% wood ash? Will having a little paper ash in there hurt things or make it less food safe? 

 

6. I am thinking of adding a couple of colorants and testing those results as well. I'm going to start with copper carbonate and cobalt carbonate. I'm also thinking of trying rutile but am concerned that it contains titanium... would glazes made with rutile be food-safe? 

 

7. I've read that ash glazes are typically high-fire glazes. I was thinking that to keep all the variables the same, I would fire all the test tiles and plates at the same temperature, probably cone 9/10. I've also read you have to go as high as 11. Thoughts? 

 

Sorry for so many questions! Like I said, I'm pretty new to ceramics and this will be my first experiment with mixing my own glazes and I'm excited but also nervous. Feel free to just answer a couple of questions, and thank all of you in advance :) Betsy

 

 

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Guest JBaymore

Betsy,

 

Not a lot of time here tonight,........ but some quick thoughts.  You've pretty much outlined a full semester college level independent study project there. That is a LOT to tackle for someone "new".  Maybe slow it down a bit....or expect the time it will take to do all that well.

 

Basic scinetific method tip........ change only ONE variable at a time.

 

Washed wood ash will perform differently than unwashed ash.  Unwashed ash has more potassium and sodium still in it.  It has more fluxing power on silica.  So for a given cone end point... it "melts" stuff more.  It tends to be more "erratic" in results.... but far more beautiful.  Washed wood ash can be directly subsituted (by weight) in most glazes that call for whiting.  Washed wood ash is basically a source of calcium oxide in the glaze melt.

 

You want to keep the ash as pure as possible.... but the occasional newspaper to start a fire that then burns for days and days and day soley on wood will not really notice the added clay content of the paper.  Most newspaper inks today do not contain the toxics that they used to.  Some people do burn absolutely pure single wood ash fires......... all birch.... all apple.... all cherry.... all oak.... etc. ........... and the chemical composition of the ash of one species is very different from another species....with different results.

 

Seive the ash well.  I use many ash glazes here.... I use 16 mesh as the preliminary initial screening (windows screen).  Then thru 40 mesh....... then thru 80 mesh for most.  Charcoal impurities float to the surface of the water mostly if you wash the ash.  If you don't//// leave it in there.... causes a little localised reduction early in the firing cycle.

 

When seiving, wear a well fitting HEPA respirator and EYE PROTECTION.  Nasty job.  When it is wet, it can get really caustic on the skin.  Don't splash the liquid in your eyes!  With the liquid.... make soap ;) .

 

Cone 9 is quite adequate for most ash glazes......but of course it depends on the exact formulation.

 

Ash glazes tend to look much thicker in application that their commercial material counterparts.  Dipping and pouring are the best if you can't spray.  Brushing can be problematic...... but you can learn to flow it on.

 

Do you know what a line blend is?   If not, look it up.  Try a couple of these. Use wood ash and any clay for one.  Use wood ash and any feldspar for another.  Use wood ash and flint for another.

 

Then.....................

 

Do you know what a triaxial blend is?  If not, look it up.   Try a triaxial blend with wood ash, any clay, and any feldspar.

 

That triaxial will likely gove you fuel for a lot of further experimentation.

 

best,

 

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

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John,


 


Thanks for the reply! This response might be a bit long, but bear with me :)


I know this will be quite a bit of work. I'm actually taking a year off of college for health reasons, and most of the time I feel well enough to work on projects. I have plenty of time to experiment with glazes, so I'm taking the opportunity to do it now rather than try to cram it in when I'm back in school, especially because I'm not majoring in ceramics. I'm majoring in glass (both blowing and kiln work), but I'm interested in ceramics as well. Of course I approach ceramics as a glass artist, and the part I get most excited about is the glazing! 


 


I thought I'd share my plan with you to try to explain how it will be scientific: 


 


These variables will stay constant:


1. I will use the same base clay (probably a light colored one, but not likely porcelain.)


2. I will always fire to the same temperature (Still trying to figure out if ^9 will work, of if I need to go as high as ^11)


3. I will start with the same glaze recipe (50/50)


4. All of the ash will be either washed or unwashed. Still trying to decide on that one. 


 


So here is my plan: For EACH kind of ash I use, I will process it (sieve it well, maybe wash it), and then mix 2 or 3 glazes, each with a different clay but using the same proportions. I'll probably use one iron-rich reddish clay, one light-colored clay like porcelain, and maybe one other (Do the clays I use have to be ^9?) I will make test tiles for each of these 2 or 3 glazes. THEN, for each individual GLAZE, I will mix 2 or 3 MORE glazes, adding colorants like copper or cobalt or rutile. I will make test tiles for each of those. Thus EACH different ash I test will produce up to 27 different test tiles. I'll probably narrow it down to only using 2 different clay bodies in the glazes, though, so I will probably have closer to 18 test tiles for each ash. 


 


I figure this first round of tests will give me a starting point, and allow me to get a basic understanding of the color and texture possibilities from each kind of ash combination. If I want to refine my glaze further I can then try a triaxial blend (I do vaguely know what that is but I need to research how to do it better) to get more specific. 


 


Does that sound like a reasonable plan? 


 


So, I'm still trying to decide if I want to use washed ash or not. I see pros and cons either way. Here's what I've compiled, let me know if I'm missing anything?


 


WASHED:


pros:


1. more stable in a mixed glaze


2. less caustic glaze solution


3. maybe less runny? 


4. goes on more evenly and has more predictable results? 


cons:


1. lots of lye to get rid of somehow


2. lots of work and time


3. less character


 


UNWASHED:


pros:


1. Lot less work


2. Don't have to worry about disposal of lye


3. More erratic but beautiful results, according to what I've read


cons:


1. Need to mix the glaze from scratch for every glazing, so harder to predict


2. might be too runny/erratic and not cover the surface as evenly


 


I'm going to try to keep the different kinds of ash as separate as possible, but there might be some blends. For example, we mostly use lodgepole pine in our woodstove but sometimes a little fir sneaks in. I'll be using alder in our smoker and saving the ashes from that. I'm hoping to find some other people with wood-burning stoves who use other kinds of wood for fuel, and might also look into finding restaurants that use wood-burning ovens or smokers as well. I want to try a variety of different kinds of ashes, not just conifer ashes. I'd like to try some sagebrush or grasses if possible, because they have a higher silica content and may make a shinier glaze. Still trying to figure out the best way to burn them completely and save the ashes-I want to have another USE for burning them, not just burn them for the ashes alone. Seems a bit wasteful. 


 


So if I were to buy 2 or 3 meshes, which ones would you recommend? I was thinking 60 and 80, maybe 100. 


 


Thanks for reminding me about safety. Like I mentioned above, I've done quite a lot of glass work and know my way around fine powders. My respirator is my best friend. :) I will certainly take added measures when working with ash to avoid the caustic nature of the stuff. Eye protection is a must, and I'll certainly be wearing gloves and an apron. 


 


So when you say ash glazes tend to look much thicker in application, do you mean that I need a THINNER layer of glaze than normal glazes, or that I need a THICKER application than normal glazes? 


 


 


Thanks again for the reply! I know this is an ambitious project, but I'm determined to figure it out! 

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I used a 50/50 cherry ash ( form fireplaces using wood for on estate orchard) and 50 gold art. It was unwashed. It was gold with a very sugary surface. It didn't settle so I did reuse the same batch. I used gloves for glazing.

 

Marcia

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Guest JBaymore

Betsy,

 

When many (not all) ash glazes go onto the ware they look thick and "fuzzy" (for lack of a better description). So they look "too thick" if you use the visual standards you might use for glazes made out of commercial beneficiated materials. So when applied the layer will be a bit thicker looking visually. It might look "too thick" from otyher glazing experience. Is that clear?

 

My real nuka glaze is wood ash, rice husk ash, and a coarse feldspar. When glazed, the pieces look thickly flocked. If it were a more commercial material glaze.... they'd all be glued to the shelves. ;)

 

I think the starting point is to do a 10% change line blend with that ash sample and the clay sample... not assume 50/50. You might find that 60/40 is better or even something else.

 

For seives for ash glazes I'd have a frame with window screen.... 16 m. A 40m, a 60m, and an 80m. 100 m is overkill for most.

 

While there are possibilities for stuff at higher cones........ cone 9 is fine.

 

While you certainly can use clay BODIES for the clay content........ you'll find it far less labor to use some CLAYS. Get something like dry bagged Goldart, a ball clay, a kaolin and so on. Ditto for anything like feldspars and flint. Clay bodies often have stuff like grog in them that you'll have to screen out for glaze useage. And taking them from wet to dry, crushing them, and then seiveing them is laboe intensive. Wet methods are not much less so.

 

Ah,... you're glassblower. Years and years ago I learned to blow for fun when I was employed at Massart in the ceramics department........ had the wonderful opprotunity to work with Dan Dailey a bit. Massart had a great glass lab. Dan was our department chari in 3-D for a while.

 

best,

 

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

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John, 

 

Thanks for clearing a few things up! Still a bit confused on the "thick glaze" thing... do I need to apply less glaze than usual or more glaze than usual, or does it not matter? 

 

Thanks for bringing up the point about clay BODIES vs. just straight CLAY. If I wanted to use 2 or 3 different kinds of clay (one iron-rich and one light-colored), which would you recommend? 

 

Perhaps I'll start by doing the line test with one kind of ash, and then see what the best results are there and use that formula for the rest of the samples so they're all the same. 

 

Yep, glassblower here. :) I've actually been doing more kiln work than blown work in the last couple of years because I've been having a lot of health issues, and it's tough to blow glass for 10 hours a day when you have very low blood pressure and are anemic. It tends to lead to fainting. So, I embraced kiln work and I absolutely love it! Hoping to figure out all this health stuff soon and be able to blow glass again eventually, though. :) 

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Betsy John gave me recipe 33.3 clay (lizella) 33.3 wood ash 33.3 spar as a starting point

 

Well didn't have enough spar with me so I subbed Some neph Sy, I only strained large chunks of "charcoal" out of ash. Used common kitchen strainer. I didn't wash ash, and since the wood recipe,is secret they won't tell other than it's mostly oak. I got my ash from a proper southern BBQ joint. I was loose with ash and choice of clay body in attempt to make a looser glaze. It actually came out too nice, prim and proper, well behaved, Speckled yellowish brown. Solid it didn't move much if at all. It's "too" good was hoping for more drippy unruly glaze which I'm making more tests with using thirds recipe as base. (This was fired at 6 ox). I'm assuming you are firing gas, and reduction?

I also plan on continuing testing. Pleas keep us updated with tests. Om 4, and gold art, hawthorn , epk are on the list along with colorants.

 

I have access to some cypress ash (taxodium distichum). Oak ash is combo of local quecus species. But I'm told "BBQ" wood blend/ mix stays relatively consistent

I have quantity of this ash if you want some.

 

Why do you need to mix fresh every glazing with un washed?... Mine settled over 2 months but didn't hard pan, I was able to get it back, hand mixing.

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Biglou13, keep in mind I'm a total beginner here ;) I don't completely understand everything you're saying, but I'm doing my best to learn!
 
I've read several recipes for clay/ash/felsbar but I'd like to keep it as simple as possible so I want to try out just clay and ash to begin with. I don't know what neph sy is.
 
For this particular project, I want to experiment with local trees and ashes. I'm raiding woodstoves and smokers to get different kinds-my family burns mostly lodgepole pine, but I know a few people that burn mostly tamarack. I'll be saving alder wood from our smoker, and calling around to local smokehouses to see if they have any ash I can use and where they get their wood from-like I said, it's a rather conceptual project about the trees in the area, so I only want to use ash from sources close to home :)
 
I'm kind of going for a "medium" sort of glaze- I don't want one that's insanely runny, but I also do want some character. Speckles and drips are good!  
 
To be honest, I'm not sure about the firing basics. I don't have my own kiln-I'll (hopefully) be using someone else's but I still have to talk to her about this whole endeavor! She's offered up her kiln to me, but I'm not sure how she'll feel about high fires and ash glazes. If she says no, I'll have to go looking for someone else who will let me borrow their kiln for a while... there are a couple of potters in the area who might be open to it. We'll see! 
 
What are Om 4, gold art, hawthorn, and epk? Like I said, I've never made glaze before in my life so I am not familiar with many of the terms, though I'm learning fast :) 

Thanks for the offer for the ash! I think I'll be okay gathering the local stuff, though. 
 
I've read in a few places (couldn't give you specific sources though) that fresh ash glaze is not very stable and that it can go bad/change within days sometimes. But if it's working for you and your results are still consistent, I guess you don't have to worry about it! 
 

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are you firing gas or electric?

knowing how you are firing and the clay/s  you are using is important to know.

 

as far as feinds kiln make sure you fire on "catch trays"  ash can be unrully and runny but thats what make it beautiful.

 

pines for the most part can give you a natural green, providing conditions are right.

 

old mine #4 is a white ball caly

epk is edgar plastic kaolin  (porcelain)

hawthorn is a fire clay

 

i super happy you are using  the local sources, as an artist its important to embrace the local......    it just happens that epk is a local source for me  just under 1 hour drive.

 

i just glazed some pieces with old ash glaze ill get back yoou when they are fired.

 

my 33.3 recipe is percentages in weight of each item.

 

"Nepheline Syenite is an anhydrous sodium potassium alumino silicate. Although feldspar-like in its chemistry, mineralogically it is an igneous rock combination of nepheline, microcline, albite and minor minerals like mica, hornblende and magnetite. It is found in Canada, India, Norway and USSR. Thus it does not have a simple theoretical formula like soda feldspar (we have provided representative chemistry of a Canadian nepheline syenite).

Nepheline Syenite has been a standard in the ceramic industry for many years, and is very popular for its whiteness. Nepheline syenite melts lower than feldspars. For example, it is possible to make a very white vitreous medium temperature porcelain (as low as cone 4) by mixing a plastic kaolin with nepheline syenite and silica (up to 50% nepheline will be needed).

Like feldspar, nepheline syenite is used as a flux in tile, sanitary ware, porcelain, vitreous and semi-vitreous bodies. It contributes high alumina without associated free silica in its raw form and fluxes to form silicates with free silica in bodies without contributing free silica itself. This stabilizes the expansion curve of the fired body. It is an excellent tile filler and melter, especially for fast firing. Nepheline syenite is valuable in glass batches to achieve the lowest melting temperature while acting as a source of alumina.

Since nepheline syenite can be slightly soluble, in pugged bodies it can be responsible for stiffness changes during aging (although admittedly many other factors can also contribute to this). It can more challenging to maintain stable deflocculated slurry bodies using nepheline syenite than with feldspars. However, the place where you may note the solubility of nepheline the most is in glaze slurries containing significant percentages, they can gel over time and the addition of more water to thin the slurry can wreak havoc with application performance (try adding a few drops of deflocculant instead).

Because of its sodium content, high nepheline syenite glazes tend to craze (because of the high thermal expansion of Na2O). Also, since nepheline syenite has more alumina than most feldspars, substituting it into recipes means that on one hand a lower melting temperature is achieved while on the other a more viscous melt results because of the extra alumina.

The picture of the flow test here shows that nepheline syenite by itself is barely beginning to flow and melt at cone 9. However when combined with other materials it will promote melting to a much greater degree than is suggested by its performance alone. Notice that the 400 and 270 mesh particle size versions do not melt differently at this temperature.

Nepheline syenite is not available in many parts of the world and the INSIGHT ceramic calculation software instruction manual contains a lesson on how to calculate a substitution using a soda feldspar. The chemistry of nepheline is quite different from other feldspars and this is thus well worth while."

(http://digitalfire.com/4sight/material/nepheline_syenite_1069.html?logout=yes)

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I'm almost positive it's an electric kiln, but like I said before I haven't had a chance to discuss this project with the friend as she is on holiday. I'm trying to do as much preliminary research as possible before I talk to her about it while I wait.

 

I know that oxidation and reduction play a part in ceramic firings but I don't know much about it, or if that's even possible with an electric kiln. I also don't know what kind of base clay body I'll be using yet- it will be bought, though. I'm not going to try to make my own clay body just yet, one thing at a time. 

 

I don't know anything about the clays used for mixing glazes. Like I said, I am NEW to this. I'm learning as fast as I can, but that's why I'm here: to ask questions and get advice. 

 

If I only glaze the insides of bowls/plates, I don't need a catch tray, right? Just for samples? Is it something you make or buy? 

 

Thanks for copying and pasting the long description of Nepheline Syenite, but it didn't really tell me anything google couldn't haha. What I wanted to know was just a simple explanation of how it is used in this application. I gather that it is similar to feldsbars, lowers the temperature of clay bodies (and/or glazes?) but it's important not to use too much or else the high thermal expansion causes crazing. 

 

Like I said before, I think I'm going to try it out with just clay and ash to begin with. Keep it as simple as possible to really let the character of the ash shine through! 

 

I've started saving ash and once I get my respirator out of storage I'll start sieving it and processing it. Decided NOT to wash it. Meanwhile I'll go to the ceramic supply store and find a suitable high-fire clay body to do all my tests and pieces out of, and talk to them about the clay possibilities for glaze mixing. 

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Just an update: spent a long time talking to the pros at the ceramic supply store, and they convinced me to start with a recipe and start at ^6 (because apparently ^10 or 11 is very hard/sometimes impossible in electric kilns, which I'll probably be using).

 

They found me a recipe that I quite like. It is simple, but probably a little more stable and predictable than just ash and clay. 

 

Frasca Wood Ash Glaze (Cone 6):

 

Whiting...............................11.36%

Wood ash (unwashed).......54.56      

Potash feldspar..................11.36

Ball Clay.............................11.36

Silica (flint)..........................11.36

 

Optional:

Green:

   copper carbonate........4%

Blue:

   cobalt carbonate..........2%

 

I also got an Idaho kaolin to try out instead of the ball clay, just to see if it works and what the difference is. 

 

 

My plan is to make 6 tiles (well, small shallow bowls since I'll be using these glazes on the inside of plates and shallow bowls) for each different ash or ash mix I am testing. 

 

1A: the ash mixed as the above glaze with ball clay as the clay body

1B: the ash mixed as the above glaze with the kaolin as the clay body

 

Then I will divide what is left from each into 2 smaller containers, and add a small amount of cobalt and copper to each (it won't be completely accurate but that's okay, I just want to get a vague idea of what kind of color I might get)

 

This will result in 4 smaller test bowls: 

1A1: ball clay mix with copper

1A2: ball clay mix with cobalt

1B1: kaolin clay mix with copper

1B2: kaolin clay mix with cobalt

 

After the first firing of all these test tiles, I'll evaluate which ones worked well and which ones didn't, and then if I like how the added colors look on any of them I will do more tests to determine what percentage to use in the glaze for the actual pieces. I've chosen a nice and slightly grainy light cream ^6 clay body as my base for all the tests and pieces. 

 

Does that seem like a good plan? 

 

Also, at the store they recommended I just sift the ash through a window screen or kitchen strainer, and said they thought I'd lose too much ash if I try to sift it any finer and that the larger chunks will add more character. Does that seem right? 

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Guest JBaymore

See my earlier posts about seiving ash.

 

best,

 

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

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I prefer to wash the ash wet, since it's so light and goes airborn easily.

 

I think ash glazes are great, but I gave up on using real ash a long time ago. I now just formulate my ash glazes using a theoretical ash formula with whiting and such. It saves me a ton of time and gives me very repeatable results from batch to batch. I just can't warrant putting the time in to deal with real ash when mixing glazes for student use.

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Guest JBaymore

A lot depends on your ash source and what it is that you are trying to achieve with the fired result.  So we come as  always to the "test, test, test" comment.

 

Example of variables:

 

Ash source....... if logs have been skidded, they pick up dirt from the forest floor.  That dirt clings to the bark.  The dirt is full of large scale grits.  16 mesh window screening lets a lot of this grit fall right through the screen.  In shorter firing cycles.... the big chunks of ??????? ( the grit in the dirt) do not get time to become involved in the melt.  Result....... rough sometimes sharp protrusions out of the melted glaze. 

 

Fired result ...... if you like something like Japanese koge results........ the coaraser the ash and the rougher the impurities the better.  All around average "glaze" suitable for most people's definitions of "functional wares"...... 80 m. 

 

Short firing cycle.............. finer mesh ingedients will become involved ion the melt better.  Longer firing cycle, more time for coarser indgerdients to become involved in the melt.  So gas kiln in 10 hour firing...... one result.  Anagama in 5 day firing.... another result with the same mix.

 

You can seive the ash wet or dry.... your preference.  I prefer dry for seiving.  Nasty dusty operation though.  I use a lot of ash........ a number of my glazes are ash based.  My wet glaze batches are mized in 40 gallon garbage cans.  I usually seive a garbage can full of raw ash at a time.  I use a combination of a home-made vibration screener and a talisman rotary seive.

 

Mixed wet glazes are also then seived wet thru 80 mesh for the ash glazes.

 

best,

 

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

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I just processed some ash and tried something new. I prefer to work with unwashed ash, but dry sieving is difficult. And it has been windy here. So, I added a good amount of water to the ash and scooped up everything that floated to the top with a kitchen sieve, then poured everything through the kitchen sieve, bucket by bucket, and pulled off anything that didn't go through. However, I'm saving this rinse water with the solubles to use to mix the glaze. I'm letting it evaporate so it will be more concentrated and close to the amount of the water necessary for the processed ash. In this way, I hope to have an easier way to process the ash, without losing the solubles. I'm going to check the SG after it evaporates for a while. Anybody else think this will work?

 

Ruth

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I prefer to wash the ash wet, since it's so light and goes airborn easily.

 

I think ash glazes are great, but I gave up on using real ash a long time ago. I now just formulate my ash glazes using a theoretical ash formula with whiting and such. It saves me a ton of time and gives me very repeatable results from batch to batch. I just can't warrant putting the time in to deal with real ash when mixing glazes for student use.

The whole point of this particular project is testing the different results from various local ashes, so making a fake ash glaze would kind of be pointless for me ;) Besides, I have the time to process the ash. 

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John, thanks for the detailed description! Based on what you said I think I will go ahead and go finer than just the window screen. 

 

Ruth, let us know what your results are! Seems like a good way to get the organic matter and other impurities out but I'm not the expert here. :) 

 

I guess I'll just wait for a still day and head out equipped with a good respirator and a few screens. Can you buy cheaper screen materials at the hardware store? Each screen is like $20-$30 at the ceramics store, and I probably won't be using them that often after this project!

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BetsyLu,

 

I am wondering how your ash glaze experiment has played out with the Frasca Wood Ash Glaze you mentioned.  I found this in a magazine article several years ago and tried it over another glaze mentioned in the article.  The first test was wonderful and I had it for a friend to see.  They asked for a item with that glaze.  It has never worked since the first test.  The lest of issues and defects I have encountered are to many to list.

 

I finally decided that it must be a cone 10 glaze based on the results I was getting.  I went looking for it online, found it in the same article I found it in, only online instead of in print.  I kept looking and finally found it as a cone 10 glaze online here: http://www.richardaerni.com/cm94.html

 

It is with 50% wood ash and equal parts of the other ingredients at 12.5%.  I have used in some wood fire kilns up to cone 11 and I like it there, but this with the original recipe that you listed with 54.56 to equal parts at 11.36.  I even saw the numbers floating in my dreams for a while due to my frustration to repeat the original test results for my friend.

 

I am wondering if you have had better results with your testing of the glaze.  I gave up on that glaze as it was a long time back and have slowly, and I mean very slowly, been testing adjustments to get in working like I would like to see it at cone 6 and dialed into the clay body I am using it on.

 

Thank you!

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