Kelly in AK

I’m not a regular potter in the sense of day to day occupation. Summertime, weekends, and holidays are bursts of work. I’ve had to learn to pace myself better physically. If I’m doing it right the work helps keep me in shape and things are fine. If not, something will hurt and take a long time to resolve. Digging my own clay really brought it into focus. I can carry ten pound loads to my truck all day or try and carry two or three fifty pound loads and pay for it later. Doing too much in an hour leads to being able to do nothing for two weeks, the opposite of productive. So, accepting a sustainable pace has probably been the biggest thing for me. I have to do regular physical exercise. As much as I wish it, clay alone doesn’t keep me fit. Even in the summer when I’m doing a lot, it’s not all heavy lifting and wedging. I exercise and that makes the hard work easier. Also, I do everything I can think of to make clay less physically taxing. Use softer clay, arrange the space for economy of movement, throw standing, get tables the right height, things like that. Thinner kiln shelves. I’ll get that right next time I order some, haha! Speaking of videos, another favorite of mine is this one of Michael Cardew. Plopping down ten pounds of clay on the wheel, he says, with a laugh, “What a merciful lovely life it is that you, at the age of eighty one, you can still do it! I say, you get weak, but improve in cunning. You get to know where to not waste your energies.” Absolutely charming. Hope I can still jam like that when I’m eighty one.

There’s a brief learning curve to dipping or pouring glazes, the glaze itself has to be the right viscosity, you need a little preparation, and of course you have to have enough glaze. Totally worth it. 30 seconds vs. five minutes. I have had a few hilarious moments pouring glaze, watching it go everywhere but back into the bucket. As far as tips, the biggest help to me was learning to adjust viscosity of the glaze with Epsom salts. Another thing is using wax resist. I was reluctant for years, went out of my way to avoid it. I found I spent an equal amount of time cleaning off glaze (and wasting it) as I did applying wax in the first place. I only use it sparingly though.

Reduction is definitely possible, has an effect, at lower temperatures. In the albums on my profile page there’s one called “ Local Anchorage Clay” that has pots fired in reduction to cone 03. They’re vitreous, 1% absorption. The reds there are from copper, no stains. The black surfaces are from iron in the clay, no stains or oxides added. I reduction cool the kiln until around 1500° F, keeps the iron black. If not, it tends toward a dark brown where unglazed. I have found that if I reduce heavily through the firing that the clay gets less predictable. I’ll have sections of the kiln with slumping, bloating, and sometimes dunting. It’s a work in progress, I have a lot to learn. I imagine a clay with less iron would be less trouble in that regard. Presently I fire a neutral to light reduction until the end, drop 100° and hold for 30 minutes in oxidation, then reduction cool till 1500.°

I appreciate everyone’s responses here so much. Very grateful. Pots, they shouldn’t hurt anybody and they ought to have integrity. That’s my standard. Easy to use is a goal, but so is a sensory experience. Always striving for those. When they align, I’ve made good pots. Liner glazes that are a good hard glass, with little (2% or less) or no metallic oxides besides iron or zircopax. Sooner or later anything that can come out will. Underglaze for color. The clay needs to be vitreous. Pots in a microwave get awfully hot and food stays cold if they’re porous. Also, mold will grow in any crazed areas. I’ve seen it, it’s unsanitary and downright gross. The list goes on. I’ve wrestled with it. Clay should be vitrified. Cosmetic blemishes or flaws are case by case. Clusters of pinholes are a hard “no,” but a couple, on the sides not the bottom, can pass. Blisters, never. “S” cracks, I found that not firing them solved the problem of deciding to sell them as well as how to prevent them. Crawling is rarely beautiful, pretty much never. Crazing, on vitrified clay, can pass, but it’s a flaw. Greatly reduces the integrity of the pot. No one will be food poisoned, the pot will die before its time clattering in the cupboards or the sink. As far as shivering, and I know it should go without saying, but one shivering pot dooms the whole lot. Throughout the process things happen occasionally that I don’t expect. If the integrity of the pot seems intact, and it won’t hurt anyone, I ask myself if I’ll accept it. “This happened. It is how things are. This is where I’m at right now. Nothing wrong with this pot, just not what I expected. Can I accept it?” Very heavy stuff, reflective. Like a metaphor, you know? I double check the pot’s integrity with a hammer to be sure. @kswan, I’ve boxes of pots I won’t sell and can’t bring myself to smash, I’ll do what you do. Never thought of that, thank you. Ceramics therapist, I could use one of those. Haha!

I appreciate your methodical approach. I rarely use unity, it is certainly useful though. For me it tends to serve as a reality check or troubleshooting aid. I’m a long way from mastering that tool, but glad it’s in my toolbox. Your picture above is a nice illustration, two mixtures with similar chemistry behaving very differently. My armchair reasoning is you’ve got the issues of: Hymod clay really holding on to water, trying to get the clay vitreous using as little frit as possible, and using materials that are readily available and not too expensive. I’ll throw in some thoughts from my perspective, for fun. Between b0073 and b0010, I feel like 73 doesn’t have enough frit to make the neph sy go into melt. 10 has too much plastic material to dry at a reasonable speed (I am amazed that one got so tight with just 20% frit though! Powerful stuff.) I jumped to figuring how to split the difference in a useful way (60 ball clay, 30 neph sy, and 10 frit was where my brain landed). I feel the same way about introducing silica as an additional ingredient, getting the body to play right then tuning glaze and/or body if there are problems with fit. All your materials have significant silica built in. Anyway, I enjoy you giving us this window to watch the journey unfold, I’m learning a lot.

I took a long break from selling pots about thirty years ago. Now I’m back at it and things are different. It was so difficult then, I had a lot riding on each craft show and I was learning as I went. As far as how savvy customers are, it feels about the same now as then. My experience interacting with people the last couple of years, after jumping back in, is completely different. I sell a lot more with less effort and stress than when I was in my twenties trying to make it work. I have a lot of fun now talking to people about pottery, gauging the conversation as I go. Most know a little, a few know a lot. My work attracts people with a certain aesthetic, and it doesn’t always correlate to how deeply they know the process. We just talk. It goes all over the place. From the best shape and size for a tea bowl, to geology, fire, or chemistry, to the fond memories someone had in high school pottery class. My crude guess about folks who buy my work is 5% are clueless (“Oh, wait, you actually made this?”), 85% know a little, 8% know a lot and 2% appreciate what I do in a pot. All of them appreciate something though, and it’s not always what I expect. I had some plates without a foot ring and thought they felt unfinished. It was a good weekend though, so I pulled out everything. One lady said, “Finally, someone who makes plates without that ring on the bottom.” She could have cared less about most anything else. They looked nice and didn’t have that darn foot! Two kinds of sales bring me heartfelt satisfaction: 1. When a potter buys my work. 2. When someone, between me telling and them looking, becomes so engaged they see through new eyes. They start examining the pots differently, turning them over in their fingers. It’s like they’re thinking, “I didn’t see that before. How could I have missed it?”

Most underglazes will fire dry and chalky looking unless coated with a clear glaze. The sample tiles for Silk underglazes on Laguna’s website show one half coated with clear glaze and the other half unglazed.

Fantastic! Thank you for sharing your work. Vitreous ware at low fire temperatures seems like a magical frontier to me, I’m delighted to see your discoveries.

I have a 4” angle grinder, with a diamond cutting blade (not a grinding wheel, a cutter) I can slice through regular kiln shelves pretty easily.

If you can read the ingredients, you can read the note below, plain as day. I can’t remember an instance where Ceramic Arts Network has published potentially toxic glaze recipes without accompanying information and disclaimers. I would absolutely blame someone who tried to pass a glaze like that off as food safe or otherwise without hazard. I’ve had probably three “Come to Jesus” pottery moments over the decades, people who knew what they were talking about getting in my face over things I needed to understand better. It’s not comfortable (particularly if you think their work is no good), but I’m deeply appreciative and grateful for those moments. I’ve stood corrected, the only thing it hurt was my pride. I wouldn’t mind helping anyone that way. This is, of course, separate and distinct from when people who don’t know what they’re talking about start giving a lot of opinions. In that case, “When someone is making a fool of themselves give them plenty of room.” comes to mind.

Sounds like you’re dialing it in nicely! I mean going from not getting above c.6 to reaching c.10 in one and a half tries is a leap of progress. At this stage you may be able to get things working the way you want from finding optimal primary air and damper settings. One step at a time, and keep good records. For good measure, make sure you give damper adjustments time before you decide what effect they’re having. In my previous kiln opening the damper would even out the temperature, but only after several minutes. I had a pyrometer on top and bottom and could watch. At first the top starts dropping, the bottom stays the same. Then the bottom begins climbing and the top cools more slowly (bottom catching up). Finally, after about 30 minutes, they even out and climb together.

Many people have wrestled with this question. Like most other questions dealing with with clay, it defies a simple yes or no, if you want the true answer. It’s rolled around in my head many years. Some thoughts and observations: There are those who make their living from ceramics. It is possible, not common. There are people who make money from ceramics, more common. There are also those who don’t make money, despite the fact they make many ceramic objects, the most common of all I think. It’s worthwhile to pencil out the math. The greatest expense is your time, far more than the cost of clay, fuel, glaze ingredients, or other furnishings. Compared to other businesses with a more guaranteed success rate, the cost of entry is not actually that high. It is initially much higher than making pottery at an institution with all the infrastructure in place though. It fools people who don’t account for the help they didn’t realize they were getting. The answer is yes. You can make a living doing clay. A few people do. Rock stars. It is more complicated than making and firing pots. You may make more money teaching people about ceramics. Some finance their studios that way. They teach, write, publish and promote, they’re hustling all the time (in a good way). Others have assistants who make the pots, while they decorate, glaze, and sign them as their own. Many people who (appear to?) make a living at clay work have alternative financing. It could be a retirement, a wealthy spouse, a trust fund, or another job. None of these things are apparent to a casual observer. They’re some ways people make it work. Do an honest accounting of your resources and what it will take to start making work and selling it. Things to consider, along with everyone else’s contributions and a grain of salt, from a guy who decided keeping his day job was the best way to make better pots.

Thera are many variants of this glaze on glazy that have no indication of their food safety (they’re not). There are also crawling, peeling, bubbling, and cratering glazes there too that aren’t food safe and have no “warning” text. In fact, it could be fun to have a contest to find the worst glaze recipe on glazy. I don’t see the glazy site as a one stop shop for people to find easy glazes that satisfy all their requirements without having to think. I also don’t see it as a teaching website for beginners. It can do both of those things to a degree, but also much, much more. It’s a user driven database that exists because of good work from generous people. Glaze recipes there have comment fields, a good place to voice concerns. The ultimate responsibility for the food safety of my glazes lies with me, and for yours, you. Now, if you’ll excuse me, I have to get down off this soapbox without breaking a hip.

I think is @neilestrick is solidly on point here. “I would set the bottom shelves up about 2" off the floor, and block off the space under the shelf along the burner ports.” The fuel needs room for combustion. Space around the edges of the shelves is critical. I imagine the space above the burners is designed as combustion area, so don’t extend shelves into that zone. It may well be that the back shelf was too high, making that space a primary combustion zone. It would make sense to me that opening the damper cooled the kiln, heat pulled off the floor right out the chimney. I wouldn’t block the inlet to the flue at all, use the damper to regulate that. The height of the bagwall you made may be overkill (gut feeling tells me it very much is), if the kiln stays too hot on top, that’s the sign. If you have high and low peepholes you should be able to see it. This looks like a touchy kiln to fire, small, well insulated, short chimney. Little adjustments can make big differences. Sometimes turning down the gas can make your kiln hotter.

I have to admit @oldlady, that’s the first place my mind went! Northern Quebec is a little ways from Albany, but the earth don’t care. Could be the same stuff. If a pot’s antique and dark brown, it’s Albany slip. Potters all the way down in North Carolina would trade for it, way back in horse and carriage days mind you, to make their “frogskin” glaze. Whatever the case @cafedunier, it may be as useful as a glaze ingredient as it is a clay body.

Definitely starting to melt, that’s the shine. It might make a nice cone 6 glaze if you add some frit to it. You’ll have to do what @Min said and fire samples at different temperatures to find out what cone it matures at. That’s if you want to make pots out of it. Other basic tests, like for plasticity and shrinkage, help you decide what you can do with it or if it has to be adjusted with other ingredients to work. For example, a lower firing clay could be mixed with a higher firing one to get a mid-range clay body. It’s cool you found clay right in your backyard!

My two cents, staggering your shelves is good, keep doing that. Space for combustion is good, I think raising that bottom shelf is the right instinct. I’m still not quite clear on the exit path of the flame, I think you’re saying it goes down through the perforated floor. A couple questions, is it forced air or natural draft? And, was there a great difference in heat from top to bottom?

Car kiln is the dream, the next iteration of my kiln building journey. Mine’s a front loader, low to the ground, load it on my knees. The top shelves are what get me. The kiln at school is a giant Paragon Viking. I don’t even use the bottom shelf, it’s too dang deep. 6” off the bottom is where I start.

My high school (graduated 1985) had a home economics room, complete with stovetops, ovens, and sewing machines. It had a well equipped wood shop, and a separate “industrial arts” lab. Two art rooms, one for fine arts and another for ceramics. It’s important to know the context of this was soon after a major oil boom in Alaska. A few years ago I was able to peruse the school district’s surplus warehouse. I was surprised by the number and variety of stationary power tools that had been removed from schools. What I see now in schools that’s analogous are robotics labs, 3-D printing, and CAD design spaces. Maker spaces. Definitely some hands on skills happening there, just not the kind I grew up with. Art rooms and ceramics labs still remain. Thankfully.

Not to mention when you find honest to goodness clay minerals that are 2 μm and larger! That’s called silt, by the geologists, and it sure ain't clay. Looks like it. Feels like it. Don’t behave like it though. You gotta squish that stuff between your fingers Ryan! Put it in your mouth to feel the grit. Make a pinch pot out of it and fire it. Then you’ll know for sure what you got. All hillbilly talk aside, my point is there are no substitutes for field testing. There was a great deal of data generated after WWII on Alaskan minerals, clay included, as well as detailed analysis of clay in my area (Anchorage) after the 1964 earthquake. That data has been helpful, but didn’t teach me how to differentiate the most useful clay materials from what it’s inter-layered with. It was hands on collecting, testing, and comparing that led me to being able to gather useful clay. A seam of excellent clay may be between layers of silt that, to the eye, are indistinguishable. Further, my recent post in “Wild clay processing” illustrates another caveat on relying on data alone. It is recorded from more than one source that refractory clay is available from the Sheep Mountain site. Enterprising people in the 1950’s made firebrick from it. I got some delightful clay there, it threw beautifully without any additions or alteration. No cracking or appreciable shrinkage. Curiously, it didn’t settle when I tried to make terra sig from it. It melted around cone 02. Not refractory at all. I surmise I was near the source of kaolin, but not near enough. It’s also a place gypsum was mined. Get your shovel and go have some fun.

I should give this a chance to be a qotw, but I can’t help myself. I teach art in a k-12 school. You wouldn’t believe the post-pandemic struggles children are having with things you and I would consider simple. Scissors, tying knots, folding paper... using a paper clip! It was getting bad before the pandemic, now it’s undeniable. Ask art teachers, kids (in the USA, at least) are losing fine motor skills with their hands. They are definitely getting better at navigating digital user interfaces though.

A white glaze I’m using now is based on glazes from John Hesselberth. It may be one of his glazes, I can’t remember. I just know I like it and it works. EPK- 32 Ferro frit 3124- 31 Wollastonite- 23 Silica- 14 add: Zircopax- 12 I snapped a couple pictures of it from a cone 6 soda fire. The speckles are from the clay body. It’s a dark iron rich body mixed half and half with a white stoneware. The dark clay bloated awfully by itself, mixed with the white clay I regularly use it turns out ok. The glaze is satin matt if slightly underfired. As for stacking your kiln, I suggest you make a new post in “Equipment Use and Repair,” posting any and all pictures of the kiln will help people answer your questions.

I don’t really have any idea, I think looking at glaze recipes is a start if your aiming at using the stuff in a glaze. If you’re looking to make straight up glass, here’s a clip from Britannica: “soda-lime glass, most common form of glass produced. It is composed of about 70 percent silica (silicon dioxide), 15 percent soda (sodium oxide), and 9 percent lime (calcium oxide), with much smaller amounts of various other compounds.”

Dang. It’s a hard problem. Sealing a porous container in a way that’s safe for everyday use with food. I’ve tried, never found a satisfactory way to do it. Ultimately, my solution was to achieve the surfaces I wanted on vitrified clay. Lining a storage container for oil (or whatever else a consumer puts in it) deviates considerably from the intended use of the product. Will the oil degrade it over time? How’s it going to hold up storing vinegar? How many dishwasher cycles will it go through before it is affected? What if someone decides to put it in the microwave? Does the product say it needs to be reapplied periodically? If so, what is the plan for that?

I do cone 6 reduction soda firings. It works fine. I don’t believe the firing range is any more prone to defects than cone 10. Mid range firing is developing rapidly, over decades rather than centuries. @neilestrick hit the nail on the head. It’s worthwhile to give it a try. You’ll see fewer glazes on glazy designed just for c6 reduction, but they’re there. One big difference is c6 glazes are mostly fluxed with boron instead of feldspar, so that means you’ll need some frits in your workshop. I get by fine with just two: Ferro 3124 and 3134. Gerstley borate works too, I gravitate towards frit based glazes because they’re easier to fit without crazing. Strontium and wollastonite are a couple more flux ingredients that see more use at cone 6. Natural ash melts above cone 6, but there are fake ash recipes that appear to produce lovely rivulets just like the real thing. Another note on the brown clays, like Neil said, they go darker in reduction (a buff colored clay in oxidation looks iron rich in reduction), but some real dark ones can also bloat and pinhole glaze pretty badly.