In this video, I build and fire a sawdust kiln. The kiln is built from brick. It's a simple design and easy to construct from reclaimed bricks. I bisque fire some stoneware, terracotta, porcelain and raku greenware pots.
Looking at the number that survived and how well they turned out, I think more adventures with sawdust are well justified. Good 'ealth, John Warner, Australia
Impressive that such a seemingly simple kiln could burn the wares to ceramics. Just a sidenote, the metal sheet and grate seems to be galvanized, if so, be really careful about the smoke/fumes when it's placed in a fire, the zinc used to galvanize the metal is rather poisonous when it burns off.
I have made some pottery out of garden clay and fired it in the pit that the clay came out of, it was just as successful as building a brick kiln without the need for bricks. This was 58 years ago when I was 20 years old. I used the clay that I had refined by adding water to the clay that I had dug from the clay pit and allowed it to settle in the pit without having to keep it in a bucket since it came out of the ground and no harm was going to happen to the clay in the process. It enabled me to refine far more clay than I could have made in buckets, without the need to buy a bucket. All the stones and sand settled on the bottom and any vegetable matter came to the surface that was easily removed with a sieve. I suppose I could have managed to keep the clay separate from the pit with a sheet that would have kept the clay free from worms and insects, however I think that this would have been frowned on by my mother. Unfortunately I do not have any examples of the pottery that I made in this way, it having been so very long ago. And the pots were only biscuit fired, the pit having been far to difficult to regulate the temperature sufficiently for glaze firing.
Being so starved for air, I wouldn't imagine that it got very hot. It would be interesting to know the temps you can achieve with this setup if you use a thermocouple next time. It's great to see folks experimenting and using simple methods. Thanks for sharing it with us.
You’ll get a higher temperature if you design the kiln so it lets in air at the bottom, creating an upward draft. Of course, you may or may not want that.
Quite interesting and informative too, just wondering if one was in a rural setting where there are no carpenters, what are the other alternatives to sawdust, maybe dry cow dung or dry dense-grass???
You can experiment with different combustibles. You'd probably find nice different effects with different materials. Some rural potters pit fire with dung.
Nice vid. All the interesting bits, none of the fluff. I like it. I also like the effective salvage/reuse of the bricks. Real good catch. Super practical. Algorithm must've got me here, since I've recently been doing some intense looking at foundry furnaces/refractory cement/clay/kilns/pottery and related "make things really really hot" technology as I get ready to build my personal "ultimate goal" multi-fuel foundry furnace. The coffee can one is OK, but as I do things, I figure out new things to do with the things I just did, so I need/want something a bit bigger, hotter, and altogether better to do 'em with. I've got the required materials, now I need to get a break in the rain long enough I can get the cutting and welding done. (I don't dare do it inside the *OLD* wooden barn, which is the only thing other than the house that's even remotely like shelter - have to do fiery/sparky/burny things outside and well away, which means "when it isn't raining", particularly when there's gonna be electricity (and therefore, extension cords) involved.
I really like that design of kiln, may have to give it a go. Great video and presentation!! I love the blackening from the carbon, gives them a great look and that ancient style.
The best I have seen for a small kiln. I have just gotten back into throwing and building and don't have a BIG kiln, but do have lots of bricks. Thank you!! From cape cod
Just my $0.02, find a local woodworker, or woodworking shop. As one myself, I either give away my sawdust my dust collector catches to local farmers, or just toss it. I’m sure you could acquire more sawdust than you could ever use in a kiln!
I was also wondering why she didn’t space the bricks out more to get air flow for a hotter fire. I personally would have put not only sawdust but a good ring of charcoal around everything, hotter fire.
Thank you. This is a beautiful exploration in the elemental aspects of the material realm! From EARTH with WATER one fashions vessels with utility and purpose. From this Earth and this water, trees grew and AIR was produced. From there to sawdust and still more Earth and water fired into brick a kiln is made and set alight. EARTH, WATER, FIRE, AIR interact under SKY and the elemental magic of time transforms these labors into ceramic. The product of which will outlive its creator and bring joy to all who have the good fortune to have held all of this wonder in their hearts. Beautifully done! The purpose of life, to experience the experience of the experience is to become experienced through the senses of SIGHT, SOUND, TASTE, TOUCH, and SCENT not only of its production, but also of what these jewels can contain. The sweet wines, butter, honey and vinegars. For all come from soil and inevitably return to sol from which pots such as this can be fashioned. May my dust be so lucky! Cheers E ॐ त्र्यम्बकं यजामहे सुगन्धिं पुष्टिवर्धनम् | उर्वारुकमिव बन्धनान्मृत्योर्मुक्षीय माऽमृतात् ||
I love your channel and website. I live with roomates, in a rowhouse in a small city, so an electric kiln is just about out of the question. Thankfully we do have a small backyard. I think I'm going to build a steel trash can style raku, per your tutorial. Mine will probably be a touch smaller, maybe 20 gallons. I want to learn to make Ocarinas and kitchenware. Although I enjoyed this video, my neighbors probably wouldn't appreciate the smoke.
A very nice result, thanks for the demo... My only issue is your steel sheet appears to be galvanized, you really shouldn't expose zinc to high temperatures as it can cause Metal fume fever (I know you are not in a confined space but I think it’s best to reduce any chance of exposure)
@@ThePotteryWheel It's probably better to use non galvanized steel, if the galvanized has been exposed to direct heat (on a bonfire) then it should be safe to use afterwards... personally I like rusty steel, the various stages textures and colours can be very inspiring
This was a nice video. I liked the out come of the firing. When you said it was a bisque firing i was expecting you to clean them up and glaze fire them . Still a cool video.
8:50 I almost always build fires with the two "log" method. Select two objects, they can be logs, or rocks, or whatever, something between your wrist and half that in diameter. Space your two logs 3 or 4 fingers apart. If it's windy, put them crosswise, closer together, with the fatter log up wind. If there's little breeze, put them with the wind. Put your fluffy tinder between the logs, where it can't be crushed, then stack your kindling over all that, leave a hole to light the tinder, and add more tinder if you need to. That's it, just light it. If the tinder is burning up and hasn't lit the kindling yet, it's easy to tuck more tinder in and keep your mini stove going till the kindling takes.
Thank you for this wonderful video! These pots are gorgeous, too! With this being a bisque firing, would you have to fire them again to make them usable/less fragile?
Loved this! Thanks for the detailed information! I've been trying to build a small brick kiln for wood-firing, and this is by far the simplest, most affordable small brick kiln I've seen. I have a variety of stoneware and wild clay pots to fire. I wonder if you could put some charcoal in with the sawdust to increase the temperature for stoneware? Although that might also increase the breakage rate...I also make my own charcoal so I've got loads of the stuff, and I know it burns about 200 degrees hotter than wood. I also wonder if using a brick or two with the holes in them as air inlets or "mouse holes" along the bottom perimeter of the kiln (you could plug them up with clay or cover them somehow when the fire burns down to that level or to create a reducing atmosphere) would let more air in and the fire would burn hotter, if you want more vitrified stoneware. Maybe the thermal shock could be reduced by pre-heating the pots in the oven or over an open fire for. few hours first. I guess I'll have to try it and find out!
i'm really curious to hear more about how this went for you. i have built a brick fire 'kiln' but yet to have success. first lot has just all exploded... good idea to preheat them near an open fire.
@@MsHan71 I've built a small version of a cross-draft kiln with clay bricks lined with firebrick. I used a small fire to slowly heat the kiln up to 100 C, then slowly built the fire with hardwood (maple and alder) branches and lots of airflow (use bars to support the wood above the coal bed or ash pit) until the ware chamber was at 900 C. Held that temp for a couple of hours, with flames coming out of the chimney and the peepholes, and then started closing up mouse holes and chimney to induce reduction. I managed to get to 1100 C by digital pyrometer. This is hot enough to vitrify or even melt some earthenware, and hot enough to bisque stoneware and porcelain. I'd like to hit 1200 C for stoneware glaze firing, but we'll see. Kiln must be well-insulated and protected from drafts, cold outdoor temps, and rain. Pots should be thin-walled, thoroughly bone dry, and preheated slowly with plenty of ventilation until the free and chemical water is gone. That will largely solve problems with explosion and spalling.
You can use charcoal to get a higher temperature in your kiln, though your chances of breakage will be higher, as you guessed, unless you preheat the pottery around the fire for the initial burn or in your oven. You can also provide a lot more oxygen for hotter burning if you don't want a reduction atmosphere.
You will not get above bisque temperature, if that, with a kiln resembling this one. Stoneware requires a much more sophisticated kiln, as described by Pipsqwak, as well as long experience and much breakage before you get reliable results. Definitely preheat the pots, even if you need to let them cool a bit for handling to load in the kiln, as that will ensure all physically bound water is driven off.
As I understood, you used green ware (no bisque)? If so, your success rate is fabulous! I wonder how durable they are. Do you think they could be used as a household pottery? I always thought durable pottery could only be made with only very high temperatures. Interesting video. Your presentation is very warm. It was a feel good video.Thanks!
Usable ware can be made from various clay bodies fired at different temperatures. Earthenware is lower fire and the clay body is softer (more porous) than the others. It is what much primitive pottery is made from. Stoneware is high fire and much more durable and is what most modern tableware is made of. Then there is porcelain which is the hardest, most refined and highest firing. All clay can be burnished to close pores, and decrease absorption making the ware more food safe. This was the process before glaze was around. Burnished pottery is not technically food safe but was used for ages for food. Not to say it doesn't work, but I am certain that people also experienced illness at points. I have pieces where the glaze has crawled leaving exposed bare clay and I still use a few of them... I have a pretty strong stomach though and seem to be alright eating stuff that would make other people sick lol.
Veryhelpful and great again, thanks. I've heard a few potters say they don't use the raku clay which they said sounds weird but they said it doesn't work so well despite it being raku clay. that's interesting, isn't it? We've been pressing a stamp into the base of the pots with p for porcelain, t terracotta and s for stoneware. it helps at the end.
that was amazing to watch, thank you for showing us! i do have a question for you-- can you use this technique to make food-safe pottery? i want to make mugs and bowls but don't have easy access to a kiln in a studio and was wondering if this would be a good alternative. If not, can you suggest anything that might be? thanks again for your expertise!
Hi Rachel, unfortunately, the pottery fired this way won't be food safe. Where about are you based? check out this article, it's got some ideas on how to find a kiln firing service. I hope it helps! thepotterywheel.com/10-easy-ways-to-find-a-pottery-firing-service-near-me/
You can use a brick kiln or pit fire to make food-safe pottery, you just have to glaze it with a nontoxic glaze to make it safe. Look up videos here for salt glazes and ash glazes and you'll find fairly easy ways to do that, though you'll need a hotter fire (more fuel for longer, with plenty of oxygen) for a salt glaze. Ash glazes should work at the same temperature as it takes to turn the greenware to ceramic. Check Andy Ward's videos for several outdoor firing approaches, though he doesn't glaze.
I don't know if you've checked him out but Andy ward has a fantastic video that might be able to help with the explosion of one of your pots. I just thought maybe that would help
While I'm not a specialist in pottery, I do quite a bit with refractory and am a bit surprised this actually worked. The top layer I would imagine benefitted most once the shavings cooked down and temperatures normalized while being fed from beneath, though I fully expected the bottom layer to be rather mushy. Very interesting! I would have thought that this would need periodic vents (moreso than chance misalignments) for air circulation to sustain combustion, as it's really up to nature's folly at hot and cold spots within. If you happen to still have any of those pieces and have or know someone with a multimeter, I'd very very intrigued to see if any of them register resistance from the embedded carbon layer.
This was some 58 years ago, when I was an art teacher, the pit wasn't just a hole in the ground it was quite large, large enough for me to Bury the remainder of the Morris eight in, from which I had removed the half shaft and break drum to make a pottery wheel out of. Also I had disassembled the morris eight Into its component parts so that it could fit into the pit. Also wasn't needed as a kiln anymore since, by this time I had bought a kiln. The reason for me buying a kiln was because, as I said in my earlier comment, it was only able to biscuit fire the pots since the temperature could not be controlled with sufficient accuracy enough to glaze fire the pots.
@@barryducret1052 I'm guessing this was a youtube faux paux of random comment replies, but it took me a moment to register a Morris was the car and not eight unsavory but notorious clay-wielding potters that need substantial justice. 😁
Amazing work, I really appreciate how simple and effective it is. Did you preheat the pieces before you put them in the kiln, I mean the candling process ?
@@ThePotteryWheel okay, sorry for that. Then how much grogged or temper you added? And how long they stayed after making till firing? Sorry for asking too much, but I really need to know as I have been cracking my pieces in th firing proces and I need to know more about wood fired kiln designed if you know any pdf resources. Sorry again, and than you for you patience and help. All support and love.
Hello! Great video for anyone wanting to try this method. Plan on using what you showed in your video for my pieces. Are you able to include the complete list of specific materials and the quantities you used in the description? I was curious of the exact number of bricks and type of wood dust (pine, aspen, cedar, other?) Thank you so much for showing us how to build a sawdust kiln!
Hi Tiffany. I use about 55-60 bricks. With the sawdust, I just used sawdust that I bought in a pet shop I'm not sure what kind of wood it is, I imagine it's pine as that's cheaper for them to manufacture I think. Sorry I can't be more specific! I think hardwood will burn longer than pine, so that's probably worth thinking about....
If you can get to a sawmill, you should be able to get effectively unlimited quantities of sawdust cheap or free. The type would depend on what the mill processes; if they make construction lumber or boards, it will be mostly softwood, and if they make furniture lumber it will be mostly hardwoods. A place that produces firewood may have a good pile of hardwood sawdust that they may have no use for.
Excellent. I live near old brick works plenty of old clay and old firebrick. Well done thank you! The kiln will be first it is great. Then try the local clay for pottery a little harder. Maybe start with a brick then a gravy boat?
Thanks Jay. It was actually a raku clay that exploded, Ashraf Hanna raku clay. Which surprised me a bit. It must have had a bit of moisture trapped in there.
i see the once that did not make it had large variations in it's thickness. I liked the one that was darkest best. Terra Cigalata according to the captions. @19:33
Thanks for the video! I can get wood shavings from a local carpenter. It is smaller than wood chips but bigger than sawdust. Do you think this will burn with the same effectiveness? I am living in rural Kenya, so I don’t have access to many other options :)
What a fantastic video! I feel very inspired now. Do you have the details anywhere, of which glazes you used? I am very new to ceramics, just learning about glazes. Is it possible to achieve lighter finishes, or will the colour always be dark, due to the contact with the sawdust and ash? Thank you! :o)
this is an old comment but if you’re still wondering she put greenware into the kiln so there’s no glaze on them! i think she mentioned that she used terra sigillata on one of them though which is like a type of slip that makes greenware come out sort of shiny (I’ve never used it myself but I know it can produce a beautiful finish!:)) also I think bisque firing like this is always gonna make the work come out dark because of the carbon from the smoke:)
just an idea but what if you kinda mark where the pots are in the sawdust mentally or just even leave a stick sticking up and make a small fire over each pot, so like five little fires instead of one big fire in the center maybe it will help something by burning different I don't know just a thought I had
Hi there, I'm glad you enjoyed the video. These pots aren't food safe. Although the clay has turned ceramic, they are still porous, and they are not glazed. Hope that helps.
Great video, thank you for sharing! What brand of heat resistant gloves are you wearing? They look like much more functional than regular welding gloves. Thanks!
Can you do saggar firing in this type of Kiln?? I read on your blog that you can do it in a pit fire, which I also believe you said was the same as this but this one is just about ground. I’ve googled it but I can’t find a straight answer and I want to make sure I’m safe
I'm afraid with such little holes for air/oxygen ingress, and that lid on top, this setup will generate a lot of carbon monoxide and some tar. Also, the heat generated will be less than otherwise it could. That said, most of the seem to have been fired well.
It looks like she's going for a reduction atmosphere here, which is a valid choice if that's what she wants. It's what she's getting anyway, intended or not.
Hi there, have a look at this article, where I talk about timings. In particular, there is a section called 'putting the lid on' which you might find helpful 🙂
You're a great brick layer still ☺️ I think if you'd have used a clean Gaz kiln, you could have had a clean result and preserved their natural colours.
the blackness is on purpose, like myself i love black pottery, the blacker the better, that is why some potter love using sawdust kiln, it's also help seal the pores of the pot and make it safe for food.
Nope it is too porous and wouldn’t hold water, it would need to be glazed and this type of kiln would get nowhere near hot enough for a glaze fire, the sawdust would also mess with the glaze and ruin the finish.
Beautiful! Did you reuse the bricks and steel metal for another firing? Or should I at least replace the sheet metal every use? Thanks for your video!!
I can't get pure sawdust so I tried using wood shavings. No idea what temperatures were achieved. Pots lower down in kiln seemed better fired than top ones. However, all pots were seriously blackened. I would have liked to have more of a mix of brown and black Any ideas???
Great proyect to do at the backyard jjj. Few questions: is it low temperature clay, or stoneware? Does the pots had been fired once to make them bisque in advance or they're just bone-dry glazed to be finished after that single firing? Thanks beforehand ;)
Hi there, it's a mixture of different clays, some is stoneware, some porcelain and some is terracotta. I put them in bone dry, but you can bisque fire them first.
If you bisque fire in this way would you then be able to glaze and fire them again the same way to set the glaze do you think? or would the charcoal bbq method be enough for the second glaze firing? Great video, can't wait to try it!
Sawdust in contact with glaze would ruin the glaze, if you want any kind of smooth surface. The temperatures in a sawdust kiln like this would be too low and inconsistent for nearly any glaze to reliably mature even if the sawdust could be kept clear of it.
Hi Lesley, I'm just building a kiln like your one. Do you think three levels for pottery would work? I mean, an extra shelf and another two courses of bricks before the steel lid. Or would it lose too much heat? Otherwise, for better cost effectiveness sawdust from an equestrian supplier would possibly work out cheaper than two bales from Pets at Home. I don't know whereabouts you are precisely but near me at Chislehurst is Speedgate / Frogpool Manor. The only problem with it would be the size of the bale for storage! Thank you so much for the video :) Best wishes, Lindsay
Hi Lindsay, re the number of levels, I think you'd just have to give it a try. I have a feeling it might lose too much heat, but you could try it out. May be just do a test run with a few pieces that you don't love that much. Thanks for the tip about equestrian supplies. But, yes, storage would be a bit of an issue. The space I have is already bursting at the seams with 'stuff'!
@@ThePotteryWheel Thank you! I'll probably try it at some point - I have to actually make some pieces to fire first (I was waiting on my clay). If I try it I'll post here to let you know how it went!
I don't add any more sawdust. I just let it burn. It's hard to say exactly how long the whole thing takes, as I normally light it in the morning and let it burn through the day. It's usually still hot/burning at 10pm. It burns for about 12 hours.
Any pieces put into any kind of kiln should be bone dry, unless the kiln is going to fire at a very low (relatively) temp to drive out all moisture before firing. I raku fire with pieces generally about 1/4" thick and rarely have anything crack or break. I also preheat anything going into a raku kiln.
Hi there, these aren't actually fire bricks. They are just builders bricks that I picked up for free from someone local who wanted to get rid of them. Sorry, I would have liked to use fire bricks too, but they are very expensive. These seemed to work ok though...
