Just Another Day

We share our last meal of stuffed Zucchini flowers. This time with a somewhat asian flavour profile, less cheese and more tofu. Ms. Kang feeds the chickens, we say our goodbyes and deliver her to the train station. There is a train service, more or less direct to the airport. We come home and start to shell todays harvest of hazelnuts. Just another day with so many jobs to do.

IMG_4381 IMG_4386

IMG_4393 IMG_4403

IMG_4410

I spend a bit of time weeding and watering in the garden, then harvesting the endless procession of ripening tomatoes. Another batch of passata is on the way. I take the time to grab a handful of bouquet-garni from the garden along the way.

IMG_4415

I finally get some free time to sort out my glaze tests from our recent glaze firing in the solar-fired, electric reduction kiln. They are all quite good, actually very good. These are all glazes made from my local stones, collected around the shire where I live. I’m very pleased with the latest version of my Kangaroo Blue glaze (see earlier post, Kangaroo Blue. 12/12/18) and the Bindook Porphyry pale limpid celadon. Not too bad for a 5 hour solar-powered firing.

IMG_4412

Ms Kang has left the building. We’ll miss her.

Our New Intern from Korea

We have a new intern working with us this January. Our visitor is Ms. Kang from Korea. She has come here to experience our sustainable approach to life and our ceramic work.

We have been working together crushing and grinding porcelain clay body and glazes from local rocks, throwing pots, working in the vegetable garden growing our food, cooking the food that we harvest and doing a little bit of sightseeing as well. The three of us have been doing some tourist activities together, like a trip to Sydney with a ferry ride on the harbour, and a trip to the local National Park and the south coast beaches.

Ms. Kang has been learning to use our foot-powered ‘Leach-style’ kick wheels.  We have just finished making sufficient clay work today to fill the solar powered electric kiln for a bisque firing. Last week we calcined some local white granite rocks, to make our local blue celadon/guan glaze.

Pretty-much life as usual, but with a hard-working and dedicated student-guest.

IMG_4109

IMG_4115

IMG_4238

IMG_4174

IMG_4158

 

 

 

 

Solar fired electric kiln, reduction glaze firing

We have fired the solar-powered electric kiln to stoneware in reduction for the first time.

This all happened a few weeks ago, but I got distracted by the arrival of the new electric car, so I’m a bit behind in writing all this up.

The kiln worked perfectly, just as I had hoped. No problems at all. I had it packed with domestic sized items, cups and bowls, plus a few clay and glaze tests to see how things worked. Plus a spread of cones to see the temperature variations throughout the setting. This is only the first attempt at a reduced stoneware firing in this kiln, so it is new territory for me. I will need to test out the many options available to me to get the most efficient firing time with the best results, using the least amount of gas for the reduction, while achieving the best reduced colour.

I decided to try a fast firing, just to check out how fast the kiln can fire. It took 3 1/2 hours to get the 1,000oC and then I set up the pilot burners to start the reduction atmosphere. The burners clipped into their mountings easily. I was careful because the kiln was quite hot already at this stage in the firing. I made the mounting so that  one simple bolt can be slid into a hole like a pin, and the mounting is secure.

The burners lit easily off the kilns heat, I didn’t have time to click on the lighter to get them started. I had built a few different sized flue holes in 3 separate damper tiles. I had made a few tests at room temperature with the different sized flue holes.

A 12mm hole with a 5 kpa pressure. A 25mm hole with a 10 to 20 kpa gas pressure and a 32mm hole with a 20 to 35  kpa gas pressure. These settings were made at room temperature in a cold kiln, so I expected to have to make a decision based on the new volume of expanded gasses at the higher temperatures.

I chose the damper tile with the flue hole outlet in the top of the kiln of 25mm sq , as a starting point. Then adjusted the gas pressure to 10 kpa. This established a slight back pressure at the burner hole and a small flame at the flue exit. I also tried 12 and 15 kpa. This achieved what seemed to be a good back pressure and reduction atmosphere with a small flame at the spy hole as well, but the temperature was still climbing slowly. I decided after an hour of this to increase the gas flow and use the larger flue hole of 32mm Sq. This kept the same reduction atmosphere and back pressure, but increased the rate of temperature rise.

The kiln reached temperature in just over 2 hours and consumed 700 grams of gas at a cost of about $2.00. The electricity cost was nil, as we are totally solar here and I fired in the middle of the day, at the greatest solar productivity. But the cost foregone of lost sales of kilowatts to the grid was about $4.75, so a total theoretical firing cost of $6.75

Total firing time of 5.25 hours. A very fast firing. Not the best for good quality glaze quality, but I proved to my self that it could be done. I can now choose to fire any length of time slower than this.

The glaze result was OK. The reduced glaze colour of the rock glaze celadon could be richer and deeper, but it is excellent for 2 hours of reduction. The translucency of the porcelain was very good – considering the very short maturation time at high temperature of approximately just one hour. It was a very light pack, just to try out the kiln and all three sets of cones went over evenly at the top, middle and bottom shelves. Cone 10 right over = more or less 1300oC

The next firing will be a slower one.

IMG_3987  IMG_3990

IMG_4020 IMG_4029

IMG_4031

 

 

 

Kangaroo Blue

Last week we found a dead kangaroo skeleton in one of the dams. It was very dead and had been picked clean over the last few days, Just the bones were left. It must have been there for some time to be so totally gleaned of every skerrick of meaty substance.

This was a tragedy for the kangaroo, obviously, but I can’t change the past. I need to get it out of the dried-up dam bed ASAP, just in case it ever rains, which it hasn’t. But I had to deal with it just the same.

I decided to take it to the pottery and put it in the solar-powered electric kiln and calcine it to 800oC. I know from past experience that calcined animal bones are very useful as a glaze ingredient in stoneware glazes. Bones contain the minerals calcium and phosphorous, both of which are very appropriate additions to opalescent blue ‘Jun’ glazes. I have used my pet cow bones in the past to make a lovely opalescent blue glaze. That was part of a project to use only local ingredients in my glazes. Using my own home-grown kangaroo bone ash might make a good glaze additive. It couldn’t be more local, being found just 100 metres from the pottery.

However, I haven’t made the glazes yet.

Watch this space

IMG_3499

IMG_3501 IMG_3500

IMG_3512

The white, calcined bones fresh from the firing, and ready for milling down to a soft white powder capable of being added to the next batch of ‘Kangaroo Blue’ opal glaze.

Some of my friends have observed that I must be mad to work like this.
Maybe I’m hopping mad?

My New Book – 5 Stones

IMG_7383205 pages, 125,000 words, full colour, soft cover. Written, collated, printed and bound on the kitchen table. A very limited edition hand made book.

I have spent the last few weeks and months editing and formatting my new book. This will be my 6th book and 7th if I include my contribution to Handbook for Australian Potters.

This new Book is titled 5 Stones, and details my recent research into single stone porcelain. The book will be launched by Grace Cochrane at the opening of my show at Watters Gallery on Wednesday 16th of August from 6 to 8 pm. I have a selection of single stone porcelain from all 11 sites on show in the exhibition.

15 years ago, I discovered a white porcelain stone near where I live. It made me think about where else porcelain has been discovered and when. Over the past 15 years, I have travelled to each of the places in the world where porcelain was originally discovered/invented independently from first principles and found that they all had something in common, and that thing was a stone called ‘sericite’. It turns out that originally, porcelain wasn’t made from the white clay at all. Kaolin wasn’t involved. All the original porcelains were made from a special type of stone called mica.
My travels led me to China, Korea, Japan, Cornwall, France and Germany. I even developed communications with academics in California, Alaska and London. Then finally back to Mittagong in Australia. Near to where I started.  I have made my porcelain pieces out of these weird and interesting materials in remote villages, artist studios, back rooms, workshops, even factories. Where-ever I could track down and find amenable people using this ancient technique who were open to collaboration. 
At each site that I visited I made works out of the local porcelain stone, but I also used the opportunity to collect samples of their stone and posted these rocks back to Australia where I could process them myself and make local, contemporary versions of these ancient porcelains. I collected native porcelain stone material from 11 sites around the world and have made what I think are beautiful pots from them, both on-site, where that was still possible and back at home in my own workshop. 
This exhibition shows results of my firings and 15 years of research into these single-stone native porcelains. To coincide with this show I have written a travel journal documenting my travels. My book, titled ‘5 Stones’ will be launched at the opening by Grace Cochrane. The book stands alone in its own right as a travellers tale, as it has its own characters and arc of narrative, but also helps to illuminate the story behind the actual works on display in the show.
I have works in the show that were fired on-site in clean conditions to give very white and translucent pieces and I also have the same materials fired at home in my wood fired kiln with very different results.
4 of the 11 examples are made from porcelain that is no longer available, as 2 of the sites are lost forever and another two have complications.
I consider my self very lucky to have been able to get my hands on all of these ancient and very special porcelain materials. This will be the first and only time that all these porcelain ‘clays’ have ever been shown together in the one place.
DSC_0002_00004
Unglazed and flashed wood fired Arita porcelain
DSC_0003_01_00005
Wood fired and celadon glazed Japanese porcelain, fired in my kiln in Balamoral.
DSC_0022
Korean porcelain made onsite in Korea
DSC_0006_01_00007
Woodfired Japanese porcelain
DSC_0005_01_00006
My woodfired local Joadja porcelain, showing some carbon inclusion on rim and base.
DSC02831
Korean porcelain stone body, woodfired in my studio.
IMG_7238
Amakusa porcelain from Japan, made in Arita.
DSC_0025_01_00009
My local Joadja Aplite porcelain, wood fired with a lot of ember and ash contact. The intense carbon inclusion reduces the translucency.
DSC_0029_01_00010
My local Joadja Aplite porcelain, wood fired with ember and ash contact.

A Rainy Day in Bangsan

I wake up and its raining, not too heavy, but I can hear it on the roof and dripping from the overflowing gutters. I walk to the workshop in a light drizzly mist. I spend the day turning my bowls. It’s perfect slow drying weather.

Mr Jung is the man who runs the Bangsan/Yang gu Porcelain Museum and Research Centre. He is extremely open-minded and has a very inclusive policy of engaging with outsiders, so as to make The Research Centre relevant, lively, contemporary and internationally recognised. This is exactly what I have experienced here. I must say that while I have been here there has been a steady stream of local, interstate and foreign visitors coming through the place. The level of creative work that is being produced by the research students is excellent.

I get all my pots roughed out and almost finished. They will need just one more thinning out when they are almost dry – but not quite bone dry.

I have a little time before closing, so I go to the Museum gallery and display area, to look at some of their stock and browse some of the literature. There isn’t anything there in English, but there is a thick, hard-cover book on the archaeology of the Yang gu/Bangsan area. I browse through it looking at the pictures. It looks pretty interesting. Shame that there is no English translation. Then it crosses my mind that there is. I have it in my pocket. I use ‘word lens’ on my phone. I select the app and hover the phone over the required Korean text and it magically appears in English on the screen in real-time as I move it along. I make my way through the first part of the book, looking at and reading the captions of the pictures. That way, I get another free thousand words, sans effort!

IMG_6955

It looks like there might be something in there worth taking in. The book is just too big, too heavy and a bit expensive to buy and take home, or post. I want to save my weight limit for my pots. I just photograph some of the more interesting pages and decide to read them later.

It’s time to go, but the weather has turned pretty nasty with thunder and lightning. I rug up in a plastic bag poncho and open my umbrella, but I fear that the wind will destroy it, before I reach my digs. On the way home, I stop to try and capture the lovely image of the rain buffeting the rice seedlings.  I have 2 goes at it, the second being a short video. But I fear for the safety of my umbrella and my phone, so stop at that.

Later in the evening, when I have time back in my room. I down-load the Korean language images to my lap top and read them back off the screen in English using my phone language translation app. It’s a slow way to read a book in another language, but I muddle through, as I have lots of time in the evenings. It even surprises ME! as being one of the weirdest things that I have ever done to get research information!

DSC02743

The next morning the weather is all clear again and I see that the river is running brown with silt washed down off the higher fields, possibly even silt washed down from North Korea over the border. I don’t know how far the catchment of this river extends into the North. There are a couple of hardy blokes fishing with a net, down by the stepping stone crossing. I stop and watch them for a while, but they don’t seem to catch anything. The technique that

IMG_7090 IMG_7086

they are using seems to be for one man to stir up the stones and sediment on the bottom and try to dislodge something into the flow and then the other man tries to catch it in their net. It doesn’t seem to be working. Perhaps they are fishing for some sort of shell fish or yabbie/crustacean?

IMG_6910 IMG_6982

My bowls are finished now and ready for the bisque kiln tomorrow. I have ordered a stamp that says ‘Yang gu’ in Korean text, and have marked all my work with this and my own personal seal. I ordered it through the mail order service of the amazing Miss Kang, who arranged everything for me and had it ready for me when I arrived at her house on the way here.

Tomorrow comes soon enough. I see the kiln packed during the day and started firing last thing before we all leave for the evening.  The next day, after cleaning up my work space, I go over to the kiln room to see how the firing is progressing? I assume that it was set to steam all the pots dry overnight and will be firing properly now, possibly reaching temperature in the afternoon?

IMG_7004

When I get over there, they are already unpacking the kiln! it has fired up and cooled down over night! I’m staggered. How is this possible? It doesn’t fit in with all my other pottery experience, where we molly-coddle the pots through the difficult trauma of the firing process, taking it quite slowly, making sure that we don’t blow anything up by going too fast or causing cracks. I guess that they do this all the time and they know what their clay will take. The kiln is electric fired and has a computer ramp controller, so it fires exactly the way that they have set it to. By the feel of the bisque, I’m guessing that it was only fired to 800 or 900oC.

I can only assume that because everything was dry before packing the firing could proceed quickly. It is summer here and very warm days and nights. And all the pots are made of powdered stone and not sticky plastic clay, so they can breath quite easily. Any way, most things come out OK. I have 5 out of my 40 or so with minor cracks, most inflicted before packing, by me I think. One has a crack around the edge of the foot, which I haven’t seen in my work before and another has a tiny hair line crack in the centre of the foot, underneath. This is a remnant clay shrinkage/drying problem.

I’m happy. I have 36 pot to be going on with. I said at the beginning that I would like to get 12 good pieces to take home if I can. Looks like I’m on track at the moment, but never count your chickens!

I spend the day glazing and fettling. I go over them 3 times to get them as smooth and dribble free as possible. The glaze looks to be a mixture of porcelain stone and possibly limestone?  I also feel that there might be some wood ash in there too? I think this because it has a definite grey cast to it and micro tiny black flecks that I some times see coming through my 60 or 80# mesh screen when I sieve our ash. The glaze seems to be very thin, so I dip them twice. It also helps to get a more even coating.

IMG_6967

When they are dry, my pots go over to the gas kiln shed for glaze firing. The packing seems to take all day on and off, with so many other things happening throughout the day. It’s all packed by 6.00 and ready for firing.  The gas kiln is fired manually, so it will have to wait until tomorrow to be fired through the day. It’s about an 11 hour firing to cone 7 or 1230/1240oC. in reduction. They use a digital pyrometer and draw trials to measure the temperature and heat work. They told me that they fire too cone 7, but they don’t use cones here?

IMG_7006 IMG_7010 IMG_7050

This facility has a comprehensive range of very good equipment and the staff are really hard-working, efficient and friendly. I couldn’t have found a more fertile and supportive place to study.

best wishes from Steve in Bangsan, Korea.

Winsome, Loose Some

We have unpacked the latest firing and it was largely good, some of it is quite good. A bit of it is very good, but as always there is the odd disaster.  I sport a winsome smile.

One single disaster was completely my fault. I made up a batch of glaze that has always been straight forward. Porcelain stone and limestone. I got distracted when someone called in and It seems that I forgot to add the limestone, so I have a bowl with what is essentially a coating of porcelain body. Not attractive.
The walls of my kiln are slowly dissolving with the build-up of wood ash. But not bad for 60 firings for home-made lightweight insulating refractories made from local bauxite!
Another casualty this firing was a piece of wall that spalled off and landed on the lip of one of my cups. I may be able to recover it with some judicious grinding and polishing. However, I ask myself if it really is worth half an hours work to make a 2nd grade mug worth $10 out of this ruin? It is quite pretty though. I may decide to spend a bit of time working on it and keep it for myself in the studio. This ‘mishap’ is not my fault, except in that I chose to build my kiln out of my own inferior, local, hand-made, fire bricks
img_3730  img_3728
I usually test all new batches of glaze that we mix up, before using them on-mass. I did just this last week to test all the new batches of domestic ware glazes that we were about to use to glaze all the pots for the next firing, destined for the Southern Highlands Open Studios weekend sales. I fired the little portable wood fired kiln with test pieces and small bowls. They all worked perfectly and melted well. The colours that i get in a 2 1/2 hour firing in reduction to stoneware, cone 10, are not as clear and intense as what we get in the bigger kiln firing for 16 hours and with a much slower cooling. However the difference is only really marginal and the faster firing is just fine for domestic ware.
I photographed both sets of tests and there isn’t a whole lot of difference. There is better reduction, especially for carbon sequestration glazes, in the longer sustained reduction firing, and the granite and pegmatite celadons are richer. Funnily, the ching-bai porcelain glaze, on the right, looks pretty indistinguishable!
The tragic, sand-paper-like porcelain-stone glaze, sans limestone, was made up after this test firing, as an afterthought, so missed out on being test fired.
img_3741 img_3558
We have just re-packed the kiln to fire again. This firing will have what I hope will be a new opalescent jun ash glaze. Here’s hoping! Ash is always so variable. We have to test each batch of ash and find the differences from the last batch, then alter the recipe accordingly. What is sometimes a blue opalescent glaze can quickly become a yellow crystalline glaze or a white matt. It changes from ‘nuka’ white through to transparent green glass with minor variations  of ingredients. It always requires felspar and silica to be added. Luckily, porcelain stone is largely composed of felspar and silica. I love it so much when it works!
There is something so rewarding about using the ash from the fire that cooked our dinner to make our glazes! There is something so truly organic and particularly rounded about the concept of waste-not/want-not, and self-reliance about this. Glazes like this are firmly embedded in my sense of place and my sense of self-in-place.
I couldn’t want for more – except perhaps a more reliable and richer opalescent blue?
img_3779 img_3775 img_3768
I pass the glaze through a fine sieve and although we have already dry sieved the ash beforehand, there is always a lot of material that refuses to pass through the fine screen. I scrape it off the mesh and put it in the large mortar and pestle. I give it a good few minutes hand grinding, until it doesn’t sound or feel gritty anymore. I know from past experience that it still will not all go through, but a lot of it will. I was lucky to see this 450 mm dia mortar and pestle in a junk shop and snapped it up. It’s a beauty! It dwarfs my Leach kick wheel.
img_3732  img_3733
The kiln is bricked-up and ready to fire now. The weather is a bit warm and dry, so we decide to post-pone the firing until Thursday when a shower or two and some damp weather is forecast. This will be a much safer day to fire.
Ashes to ashes and lust to lust
Steve and Janine