Upgrading My DIY Pottery Kiln - How Hot Will It Go?
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- čas přidán 27. 07. 2021
- I made some changes to my DIY pottery kiln, allowing more oxygen to reach the fire. This results in more efficient combustion, less smoke and higher temperatures. In only the second firing of my backyard kiln I reach even higher temperatures than the first time. Now I am making plans for more changes to the kiln to try to reach higher temperatures.
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Thanks for all the advice and tips. I will be implementing some of these into the next round of improvements. My goal is not just to easily reach high temps, but to have a little kiln design that others can easily duplicate in their own backyards. So simplicity and inexpensive materials are essential.
Tip!
I love the content. The amount of air flow is going to be just as important as how the air moves inside the chamber.
You like experiments, so please try this one!
The next time you are in the car, roll down different windows about half an inch in varying combinations and feel how much air hits you in the driver seat (best done while on the highway).
Crack the front two windows. feel the air currents in the car. Roll them up.
Crack the two windows on the driver side. Feel the air flow. Roll them up.
Crack the passenger windows. The Driver Side (in America) is going to get the most flow, particularly over your left shoulder and left hip. Roll them up.
Crack the front driver side and rear passenger... roll them up.
Crack the passenger front and rear driver.
Where the air flow enters the system is just as important as how much air moves through the system. The Venturi effect is very powerful when used correctly. Think about how the air flows over your car while driving on the highway. Think about how the air is flowing over your system while firing clay.
Andy, thanks for the videos! Just getting into pottery and love the idea of having my own small kiln like this. Have you tried another firing since posting this video? If so we’re you able to reach higher temps?
I am finally building a kiln similar to yours. It has a wider diameter. I am building it up on gravel to protect the bottom from rain water. I'm using clay mixed with wood ash for the mortar. I'm afraid I'm not the dynamo I once was, so it'll take a while. Meanwhile, I'm making a bunch of pots from clay off of my property to fire when the kiln is ready. I found one small spot of pinkish white clay that I really like. Dang, I'm having fun! Thank you! Michael
Try replacing your fire wood charcoal, which you can make for fairly cheap. If you didn't know charcoal will combust and burn hotter/faster than any firewood ever will.
Edit: You could also try laying a cheap hair dryer right outside the firebox to force a ton of oxygen into the fuel. That's what I've been doing with the mud kiln I made this week and it gets really hot really fast.
Andy, I can't begin to explain how inspiring all your recent videos, including this one, have been. I'm working far away from home most of the time lately, which leaves me very little time to try to put any of these ideas in practice, but as I get closer to retirement I'm starting to put together a setup that I hope will let me hit the ground running, and your insights have been central to that. In the last few weeks I've put a steel drum with ventilation holes in my backyard for pit firing, I've gathered a ton of volcanic rocks of a type that I think will be a suitable substitute for fire bricks when it comes to building a wood kiln, I've collected three different kinds of materials for temper, including a very fine nearly crystal-free volcanic ash, and I've found and collected from four different clay sources, two of which I'm fairly optimistic about them being workable. I'll start by doing some test tiles and trying some simple pinch pots, and then seeing where I can go from there.
I've bought an Ancient Pottery Club membership, and as time permits, I'll be taking some online courses from your site. My wife and I are both getting increasingly excited about the possibilities. Like you, we also enjoy watching Simon Leach, and it seems to me that your two approaches compliment each other very well. We used to dream about getting an electric kiln and a wheel, we probably will one day, but since finding inspiration on your channel, we're both thinking the coil and scrape method is going to be the perfect introduction for us.
Right now we're dreamers rather than doers, but you've made the inevitability of doing, within the next year, so much closer to reality.
Thanks for sharing your story, really inspiring. Thanks, and keep on watching. I hope you get time to play in the mud real soon.
Extend your firebox another two gothic arches in length. Also, it’ll get incredibly hot if you let a leafblower idle while pointed at the firebox inlet.
Thanks for the tip, I have a friend who has had great results with using a leaf blower in his firings.
I keep thinking: Can you stick a brisket or a dutch oven stew in the kiln after every firing and keep it there for about the next 6-8 hours on low heat? Just to salvage all that energy for cooking.
That is really a great idea. My old adobe kiln held heat much better than my current brick version. You could have cooked in that kiln for hours afterward.
Awesome post Andy! Extend the firebox a bit, raise the chimney a bit (getting smaller in diameter as it goes up) and put the mouse holes in the firebox, not the firing chamber itself. I am confident you will make it to Cone 04-06 in no time.
Thanks Rusty, ever onward!
A taller chimney will create a stronger draft, allowing the fire to get higher (even without a blower or bellows). Also, charcoal burns hotter than wood, so you could try using charcoal for firing- you can make your own charcoal, if you have enough wood.
As someone who ended up loving making and appreciating pottery... I'm definitely looking at cheaper options to fire then lol
I just saw this "rocket kiln" on the Uncle Mud channel; that's something you ought to emulate! I too, shall be striving to; in fact, I feel virtually like Clay Mud already!
If you extend the chimnet about 12", you will get much better draw and higher temps more quickly. You won't need a fan.
Excellent idea to add a layer of the grill at the feed area to have airflow. I think to maintain the heat at 800 degrees celsius sand is the best medium to hold the heat. we could possibly split the area of firing and the area of de-moisturizing the pottery. The heat escapes could be sealed from top and bottom of the chamber. we could also have a vent going up from the firing area so the fumes could escape. Overall it is the best klin made at home in an economical way! My hearty wishes!
Thank you for your insight.
Your fan could be blowing the heat from the bricks on the outside. A smaller fan only blowing into the fire box might help. Also the 2 bricks you moved in the bottom may need to be closed up some or mostly, they are letting in cooler air that is helping take the heat out the top. A small fan blowing into the fire box might be enough. If you consider what a blacksmith does to get a lot of heat, they only add air into the flame area. A little mortar added to the outside could hold more heat in also,
Very helpful Andy. Really appreciated that you regularly shared the time as the firing went through its paces.
Glad to hear that you enjoyed it. Thanks for watching.
This reminds me a lot of rocket stove design. With that in mind I would insulate the bottom where the greatest heat is. Could be as simple as an air space and then mud wall surrounding the kiln bottom. I'm also wondering about the fuel. We have a wood around here called Osage Orange. It is used for posts but it burns crazy hot! I wonder if a fuel source like that could push it up a notch. Thanks for these videos. I'm learning a lot and its exciting to see what I could possibly do.
Same principle as a rocket stove, convection. I am familiar with Osage Orange, I used to live in Oklahoma where it grows like a weed. Mesquite, which I am using burns easily as hot as that. Thanks for the tips!
the cross sectional area is critical the ratio of rocket stove is 3:2:1 that is percenate so the second number is half of three, etc. this is critical for maintaing draft. all the ratios not to be tight with no air gaps, study ernie and erica book
Look up Tatara- there are back yard versions. It’s for smelting iron but possibly useful and borrowable tech
Take note wood not totally burning early enough which is visible in the wafts of black smoke coming directly off your flames
The height of the chimney as well as type of wood that you’re burning, and stoking rate. I would also use the type of fan that concentrates the air into the opening of the firebox. There are many things you can do to increase the temperature, but like you say, you’re just looking for 800 C
Another excellent video. Thanks Andy! :)
Thanks, I will be making these improvements in the future.
Nice work, you could try firing with charcoal instead of timber, it usually burns hotter. Also when you have the fan on, try closing the extra vents at the bottom. Keep up the good work. God bless
Thanks for the tips.
@@AncientPottery Hi Andy I will be interested to see if these work too. God bless
Hi Andy. I have a small side flame propane kiln that works similar to yours , sometimes if I play with the flu opening ie.. opening slightly I can get a good spike in temp that sustains . Less reduction but higher temp. Just my two cents 😐
Good tip! Thanks.
Try a, venturi effect..make a larger opening in the front..which will increase the speed of the air. Or change to an electric leaf blower
People use those to get small furnaces up high enough to melt aluminum and copper or brass
This is awesome!
Thank you
I know I'm kinda late here but as with all of the other good suggestions here's mine. I believe the hottest part of the flame is the tip. Take some temperature readings higher in the kiln. If I'm correct in this by placing pottery higher you will get the higher Temps you seek. Also it will open up the fire- box area, floor space allowing for more oxygen and a cleaner hotter burn. Great content!
Thank you for this incredible idea
My pleasure 😊
And BTW that’s a really cool set up ! I like it !
Glad you think so!
I'm really enjoying this video series. Giving me solid proof of concept for my own design! Keep up the good work!
Thanks, that is exactly my goal.
Great video, will def save me some time on the trial and error I need to do for my firings, much appreciated!
You are welcome, thanks for watching
Using the leaf blower as many of your viewers have already shared should work. Also a 6" fan with flexible clothes dryer hose to direct the air flow to the firebox inlet will be more efficient than the fan you currently are using. As a last resort a DIY air venture blower will get lots of air flow and can be directed to the firebox inlet. Thanks for sharing.
I am fascinated with watching the development process. You are awesome to share this evolution and reasoning with us. TY.
Glad you enjoyed it. More to come.
well done ! I would say the slow build up to temp is due to the nature of the bricks that suck up the heat when cool. Using some form of insulated bricks or making your own, incorporating sand, clay and sawdust for example. The size (volume) and length of the wood feed also will have an effect on the temp. A longer wood feed would allow the heated air to pick up velocity and suck more air in, creating a venturi effect, also perhaps a larger wood feed opening and volume may help (though you have somehow corrected this with the later lower opennings. May also consider a slightly taller chimney (height of kiln) to create more draft (flame velocity). Just some thoughts :))
Thanks, good suggestions. I am planning another firing soon along with a few improvements. Stay tuned.
If you use charcoal and a little blower, you can melt iron, if you want. It burns FAST and hot. Probably, you want a charcoal fire with wood on top. The ratio of fuels and the amount of air will control your speed.
Put a little door in front of where you're putting the sticks in and have it just slightly open you'll get it hot faster
Hi Andy did you back those brick/pavers stone behind you? Thx for another great video learned alot.
Cone 013 (Kiln color red) Super low fire.
1850f is a cone 06 and it is used for the bisque process and low fire glazes.
You need a forced air blower piped into your kiln to achieve higher temps. These look like miniature squirrel cage pumps in a metal nautilus shell.
Hi, i have learned alot from your vids, thanks. To get higher kiln temprature i would only allow hot air to enter the kiln. I guess we could install a coil of metall pipe at the kiln exhaust and have one end of that coil at the kiln opening(air inlet) and the the other end of the coil will have a small fan blowing air through it.
Thanks for the tip Muhammad. Don't miss tomorrow's video where I will show the next step in the evolution of my brick kiln.
Hi. Andy. Have you looked at how to build a rocket stove. (Green shorts) your kiln is similar in design. Perhaps going full rocket stove will increase your temperatures. Just a thought.
My understand of "rocket stoves" is that they are based on convection the same as this little kiln. I think the same principles are at play, so not sure what aspects of a rocket stove might improve this but I will give it some thought, thanks.
I'm thinking of taking a giant, medal barrel I have and putting it on top of my chimney with a gap at the top to allow flow...sort of like the bell chamber on rocket stoves...I'm wondering what this will do or if it'll just snuff the fire.
@@crowstudios300 Sounds like it would be worth a try
I haven't read all of the comments, so you may already have gotten these recommendations. Forget about the box fan. Get a thrift store hair drier or vacuum cleaner, add a heat proof extension, and blow a concentrated stream of air in, under the firebox grate.
We have two, large, wood fire kilns at Solano College in Northern CA. They share a chimney that's about 24 feet high. It's the extent to which the draft created by the rising column of extremely hot air draws air in from the firebox that gets us to 1300C (in four days, with four cords!)
I'll build my test kiln as a rectangle for a tighter fit, and have a bigger, deeper and taller firebox, with mouse holes in the second coarse of bricks, then a couple more courses of bricks, then the opening for stoking.
We have a door that we close between stokes. Air coming in that flows over and past the fuel is unheated, and moderates the air flowing through the fuel and providing oxygen in and through, rather than over the fuel.
Fuel opening that's higher and not as tall will allow added fuel to drop down into the embers and fire, so there can be as much fuel as with bigger mouth, but not so much cool air going in.
Reducing the diameter of the ware chamber and adding at least a 4' chimney, perhaps 8" in diameter, would draw in oxygen ten times faster than this set up, and it would be lost faster, but the heat would be greater, and would transfer much more heat to the walls on the way through.
Sealing the kiln once it's extremely hot is the right thing. Maturity of clay is not only about top temps attained, but by how long
Thanks for the info. I actually figured it out using an ad box chimney, more air holes and an ash grate. But I also am done with these kilns, watch my video that comes out next Wednesday to see how I fixed it and why I gave up on it. Oh, also I make earthenware, no vitrification, and time at temp does not matter to what I am making.
I've watched metal workers on CZcams use an electric bathroom blow dryer with a tube made of sheet metal that goes over the blow dryer's tip and the metal tube goes into the bottom of their homemade forge in order to get it hot enough to work their metal.
Insulate it with clay and a clay straw mix on the outside bet you could get it to the temp your looking for
That is probably true. When I stop feeding fuel into it, it cools down very fast so the ability to hold that heat longer would a great help.
Yep, cob clay as insulation would be good as would a taller chimney. That said a train tunnel design would also help, but it's outside of the scope of the design
Id make a door for the front out of metal and bolt an induction fan from a wood stove on it. You can control the temp by the vent on the fan or its speed along with the bricks youve already modified to open.
If you check out literature on Rocket stoves, which use the same principle as this kiln, you will find that there is a formula for the proportions of the chimney diameter and hight as well as the firebox, to make them as efficient as possible :)
Thanks that's what I'm looking for, efficiency!
@@AncientPottery the batch box style rocket stove may be worth investigating
batchrocket.eu/en/
I have thought about this and I think ( to complicate things a bit) a stove pipe added to the back of the kiln would add a lot of draft, sort of like a wood stove. You could, then, close the top of the kiln while firing, retaining heat. I really want to try this out behind my shop. Michael
Yes, you are on the right track, a chimney creates draw.
Glad to see you haven't been washed away recently! What is the link to the one where you dug the Show Low clay (or made the test pot)? That really is a wonderful clay...may even beat Cannonball!
This video was shot before the rains came, but I am still here thankfully. I haven't made a video about that clay or test pot, I think I talked a little about it in my May livestream. This little Facebook video shows the location where that clay comes from fb.watch/v/3pf-XTsiO/
Very nice. What impact does opening or restricting the opening at the top of the chimney have?
You can learn to "read" the fire and adjust appropriately. Restricting the top holds in more heat, but the fire needs to maintain a good draw, so when it is burning really hot it often needs a larger opening. If the flames start licking out of the front or the side holes, it means it needs to be opened wider to maintain a good draw.
If you want to try to achieve a higher temperature you could try something I have done on a burn barrel which was to incorporate a heat exchanger in the construction which heats all of the intake air. I used corrugated iron wrapped around the outside of a drum so all the air is pulled down through the corrugated on the outside of the drum preheating it before it gets to the bottom.
Maybe if you used a steel duct for intake air which is built into the kiln chamber and have a removable cover or door to load the timber.
Just an idea, I can’t say how much increase you would get but if the air is heated prior to combustion that heat does seem to make it burn hotter and cleaner
Yeah, it actually sounds like a great idea, but I am trying to keep this kiln simple and "primitive" so I need to find a solution that is simple. Actually since I made this video I have made several improvements, I will be making a video soon showing how I am firing this more efficiently these days.
@@AncientPottery it would be fairly easy to incorporate in a new build, not easy to add to an existing built furnace, anyway as long as it’s working for you
I've seen many of your videos. Why don't you use the rocket stove design (J shape) . It can reach very high temperature with very efficient burn.
can i use floor tiles instead for the top cover? ..... wow and no smoke too
Maybe, give it a try and see how it works out. My only concern would be that the tiles might not hold up to the thermal shock of it.
You should reach 2000 F easily using a leaf blower. Just like a blacksmithing forge. I really want to build a kiln like yours, but with fire brick. I'm afraid building brick will break down after a while.
Well I’ve fired a number of times and don’t see any wear and tear on my bricks. But I’m only running it up to about 850 - 900 C, if I got a lot hotter I might.
I realise I'm late to the party here, and this may not be relevant / useful, but I'm wondering how much difference using charcoal would make. Or is charcoal something that's just not used for firing pottery?
Yes charcoal might be something interesting to try, thanks
Why not use some lump charcoal, burns hotter and cleaner?
Yes that would work well
For what its worth, I guess you've solved your problems with it now, but from my observation of this here, If flames are licking out the bottom past your brick openings? Your kiln is not drafting right and its loosing heat through the small brick vents. Use the vents early on, then later close them as the kiln comes up to heat and is better able to draw air from the fuel box entrance. Play with the bottom brick vent gaps to optimise oxygen draw, and minimise heat loss due to an easier way out for the fire to vent..
Right but it was only doing that when the fan was on. The way I fire this kiln has evolved and the last few times I have used it without a fan and am reaching my desired temps just as fast. I need to make a new video showing what I have learned. Thanks for the ideas.
@@AncientPottery Thanks for taking the time to reply.
1000 °c glazing I used to firing, can i use this type of kiln, and which material you are used for stand inside the kiln
maybe I think I could get this up to 1000 C if I worked at it. Bits of broken pottery are used for propping pots but generally since I don't glaze I don't worry about things sticking together like others do.
im new to firing clay, think we all done a little clay in school, I have a tall smoker grill out of steel with multiple levels wire shelves, it works on fire or gas propane, line it with fire bricks do you think it would get hot enough ?
Not sure. A smoker generally doesn't get super hot, right? In order to turn mud into ceramics you will need a temperature of at least 1300 F or 700 C
@@AncientPottery its steel and I was thinking of adding fire proof blanket inside lined, it already has the propane burner in the bottom and can also use charcoal wood
Maybe need a longer fuel chute. Probably a lot of heat is escaping through it, because its basically a big vent in the side of the kiln.
Because it draws like a chimney, I don't think much heat is being lost out of the fire box. But definitely lengthening it would allow me to add more fuel at one time.
@@AncientPottery
You could test your draft by restricting the fuel chute with a couple bricks once you have a good burn going, or stack a couple bricks in a chimney around the flue. I built a sandstone stove at my campsite thats pretty similar and I cant use it until its burned down to coals, because it has 2' flames spiraling out the top. It took a lot of adjustment to get the opening ratios optimal.
I wish i could also make my own kiln. I'm dying to fire my small pots that i made.
Bricks are cheap... if you can find them. I couldn't get anything but cored bricks.
Idk if you have room but I have built several small kilns out if mud even, if you have access to land what I did at first was just dig a hole and make sure the pots are next to it heating up by the fire, and then place a stone down, out your pits in it and almost enclose your pots in a case of sticks, then allow the fire to catch again, then slowly build it up till the pit it full of firewood then allow it to burn down and a night to cook
@@creepingslaytor6073
You can also stack bags of charcoal around it, just like firewood and burn it right in the bags. Youll want to ring it with some cinder blocks, or edging stones or something to contain the charcoal when the bags burn.
Do it, you can ever fire out in the open without any kiln like this czcams.com/video/SpndlM2VgHg/video.html
@@springbloom5940 look for brick pavers.
I just bought cheap materials to build an experimental kiln( will work for sure) like no otther.
As a source heat il use a forced air TLUD gasifier ,no smoke( smoke is flame thats wasted= wasted fuel).
A Tlud is quite simple to make and efficient and doesnt have to have a fan to be forced air.
TLUD is way more performant than a rocket stove.
For insulation of the kiln i use cheap Ytong bricks lined with ceramic wool so that the ceramic wool will protect the Ytong a bit since the Ytong( aircrete) its stable up to 700C.
Ceramic wool comes in different grades,somme are rated up to 1250C ( aluminosilicate) and somme that have zirconia are rated up to 1400C.
Would be hard to get Ytong bricks in USA thogh.
Very cool, thanks for sharing. I would love to see pictures.
I wonder if Native Americans positioned their kilns in the direction of the prevailing winds, to take advantage of natural air flow. I remember reading about some ancient kilns that were found in a valley, with the openings facing the direction of the wind blowing down the valley. This was ages ago, so I don't recall the details, but I think they were Roman.
A cross draft kiln! Primitive Technology has a video here on CZcams of him making and demonstrating one!
Would hedge apple work? That stuff burns hotter than the blazes.
probably would work fine but it doesn't grow around where I live so I have never tried it
Hedge apple us also called Osage Orange, and was recommended in a previous comment.
My understanding is that dense hardwoods contain more potential energy, but are best for long, slower burning to heat homes. Seasoned pine burns faster. Most cabinet shops trim the irregular edges of rough lumber, and throw it away by the ton. It'll be 16' pieces 1/2 to an inch across. It's great for stoking due to small surface area, and ease getting into tighter stoke holes. Again, smaller stokeholes admit less cool air that flows over the combustion, rather than under and through. And participating in combustion.
@@kemperstone9989 good suggestion on wood. My usual for outdoor open firings is mesquite which is quite dense.
very nice ! is it possible to glaze in small kilns like this or is there somebody on youtube who glazes in small kilns? thank you
I don't know. What temperature is required to melt glaze?
At those low temperatures you could still glaze, or glass over with some low fire glazes like stroke and coat would be dull maybe but would still create permanent color . You would be below cone 06 but you could still get permanent and interesting results.
I found some "low fire" glazes on amazon but you would still want to check them out for lead content. Not suitable for food if there is lead. you might also want to set the pieces on a shelf since glazes drip down and would probably adhere to the rebar.. I need to down load a cone chart to match up temperatures on how the kilns are performing compared to product requirements.
Look into salt glazes and Egyptian Fayence techniques :)
Look into salt glazes and Egyptian Fayence techniques :)
How hot does your wood burn? Wasn't charcoal used mostly for kilns?
Not that I'm aware of, I think most wood kilns use sticks of wood and not charcoal. No idea at what temp the wood burns, it would depend a lot on the species and the dryness among other things.
If you're still using this, tell me what temp you want to hit and I can give you an outline of what you'll need. I regularly blast my brick kiln well north of 3000*C to graphitize various carbon sources and have no more than $150 invested.
I would like to learn more about your kiln. Send me some pics, let's talk.
@@AncientPottery I'll get some stuff gathered tonight and send you an email to your listed address on your yt info if that okay.
@@C-M-E Fine, thanks
you had a big top opening and waiting for heat to raise fast
Wondering if your still working on backyard brick kiln .
I'm a BFA,ACE married to an Engineer
I am still using it but haven't made any improvements recently. The ad-hoc chimney was my final improvement, so I am pretty happy with the results now. You can see how that chimney works in this video czcams.com/video/4z3x8psUUbE/video.html
How hot does it need to get to do glaze?
Hotter than this
electric leaf blower?
Yes, thanks, that is something I have been considering.
It works great. Box fan at that distance loses speed, scatters, and misses the stoking port.
Im thinking air pre-heating is your answer.
I have considered that but have no idea how to engineer it.
Is it possible to get up to 1200 degrees with a homemade kiln?
Yes, it definitely is possible.
Thanks . Do you have a video of a Kiln that can do that. I have a project to build one in my garden :) And again, thanks for all the good videos! @@AncientPottery
By the way you won't need none of those vents when when you have that little door
IF YOU WANT HIGER DEGREES PUT A HIGH 2 HIGH POWERED HAIR DRYERS ONE AT EACH ENTRANCE. PREPAIR TO BE AMAZED
LOL, yes.
I'm not sure why you opened those side holes at the bottom of the kiln. They are probably just cooling off the fire produced by the main air intake under the wood. Also, you can see flame shooting out these holes when you turn the fan on. That flame should be going up into the main kiln instead of shooting out the bottom. At the very least you should have tried closing them off at some point and seeing what the effect was. If the side holes were closed up you would have a stronger draft from the front where the fire and the fuel actually is...
Having fired in the kiln before and after the holes, they did help. I have continued to refine my firing method in this kiln.
was it hot enough to vitrify??
No, my pottery generally never vitrifies though. I make earthenware so my goal is a bit below vitrification. I do believe that you could get the temps up there with one of these though.
No way you'd vitrified without a ten foot chimney, 36 hour firing, and a door on the stoking port that was closed between stokes. We stoke about four pieces, 18 to 24", average 3" diameter every 4 to six minutes for at least a day to even get close. Getting to from 800C to 900 takes more fuel than getting from 50 to 80C.
A slow start prevents cracking due to shock, but also brings the kiln walls up to temperature, so that they stop absorbing as much heat from the fire. Getting the whole kiln hot also keeps the heat from combustion dynamic, with a strong draft resulting from rising hot air, which is displaced by cool air entering primarily below the grate, for hottest fire.
Since you've gotten a bunch of similar comments I'll keep it short. The fan is stripping a lot of heat off the outside of the kiln since it's not focussed (basically wind chill). If you were to run a hair dryer in some black iron pipe into the bottom, below your grate, it would allow the hot air pocket around the outside of your kiln to stay there longer. You could also brick around the pipe below the grate for less heat loss through radiation. You'd still be able to add the same amount of fuel on top of the grate, and it would only increase the cost about $10 for a cheap hairdryer and some scrap pipe.
Thanks for this info. One problem with this kiln all along is that it cools off rapidly, it needs insulation or thermal mass to help it maintain heat
Great video Andy! I love watching your videos. 😀
I’m currently working on converting an electric kiln to a downdraft gas kiln with a thermal draft inducing flu (aka TDI, built inside the kiln it super heats to increase draft).
It seems like a downdraft (flu opening starting at the bottom of the kiln forcing heated gases to circulate down) and a TDI could be fun to play with in your kiln.
Here is my inspiration, www.sebastianmarkblog.com/2018/07/gas-kiln-conversion-downdraft.html?m=1
His book on Amazon has lots of great info
Thanks for the info and the link Charles. Great information.
Simon Leach
Oxygen or Air? So 21%😁 lol.
Well since I don't generally have access to pure oxygen, I'll just use regular old air to provide oxygen to the fire. After all, air is around 20% oxygen and the fire seems like it just fine.
fill with charcoal
That could be worth a try, thanks.
Throw a lump or two of coal in there
That would definitely do the trick
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2. A distraction from political problems.
Lose the political shit
I have no idea what you are talking about. I do not get involved in politics at all and I am not even registered to vote. I feel that something I may have said in this video is being misconstrued.
I don't get it either. So this is some perverse gag, and you got me.