FIRING a Bisque Kiln - A Guide for Beginners! Day 38 Quarantine Distraction Video

[Music] hi everyone welcome back to my home studio this is my day 38 of my quarantine distraction videos that I've been doing for my students and for all of you while we are quarantined or an isolation with the coronavirus right now so today's video took me a couple of days to kind of put together and get everything shot because it was the process of loading and firing my kiln so in this video I'm gonna go over a bisque firing so loading and firing a bisque load I have an automatic kiln but I also review how to fire a manual kiln that has a kiln sitter and understanding a little bit of that I do have a kiln meant my studio is in my house basement and the kiln mint is a very very important aspect to keep all of the fumes out of my house it's very important that when you fire that you don't smell the fumes in your house that is dangerous so we want to get the fumes out that's why I use my overhead vent there are under mount vents I used to have one but I do have a video on my overhead vent on how I installed it if you would like to see that it's a vent to kill I don't get anything from this I just I like it and it made a big difference to me when I started using it and it also takes out a lot of heat my kitchen doesn't get as hot up above so hopefully you find this informative dropping any questions below if you have any if you do have questions on understanding what kind of glaze can you use with your clay body the first thing that you want to do is always check your clay body what is the firing temperature to mature your clay body okay and then you can select your glaze based on that but I do have a packet it's included within a video that I put out a couple of weeks ago for my kids it was refusing reviewing glaze information for those kids so you might want to consult that because a lot of the a lot of the basics are in there so I hope you enjoy drop me any questions below if you've got them and stay safe stay healthy and keep potting if you can first of all when I load a bisque kiln I am usually doing a stacking or what's called a tumble stacking arrangement of loading as long as you're loading things in a stable way so they're not going to put undue pressure that might warp something you can stack things in a bisque kiln one on top of the other the glazed kiln is the one where you have to worry about having things touch because if you have to glazed pieces and they're touching they will melt the glaze will melt and they would end up by fusing together but a bisque kiln does not have that danger with it now the one caveat I would say is if you do have under glaze on some of your things like on the bottom of something sometimes the under glaze can transfer a little bit maybe it's transferring vapor I'm not too sure but it can leave a ring on something if it has under glaze that especially if it's a bright under glaze like blue or something on on me whatever it's sitting on so just be aware of that when I bisque fire items I often will stack things rim to rim bowls rim to rim or in the case of this because this has a flat bottom I could easily just set it right on top the bottom right on the top if I'm firing multiple plates plates I stack rim to rim it helps to keep them a little bit more stable to prevent warping also if you have a bottom of a plate stacked on a bottom of a plate and a bottom of plate that's a lot of weight that sometimes could cause some uneven heating so I think when they're rim to rim it allows them to heat a little bit more evenly a couple things to be aware of when you're loading a kiln you want to try to load it in order to get even heating so if you have maybe you have some thinner items like you have like a tray try not to put the tray the very top or the very bottom of the kiln try to put things like that toward the middle because if you have a really shallow shelf on the top or a shallow shelf on the bottom it could cause uneven heating now let's talk a little bit about the firing temperature for kilns if you are not fully aware the big difference in firing a glaze load and abyss cloade are going to be the temperatures bisque firing is the very first firing that something goes through I bisque fire all of my pieces to Kohn zero for that's typically what my glazes recommend cone zero for is if I remember right it's around nineteen forty five degrees Fahrenheit and that gives you a nice strong play body but yet porous enough that when you go to apply glaze it is soaking in some of the water from the glaze and it helps the glaze to apply real evenly now it's the glaze firing that's where you have to be very attentive sometimes when people are new they don't understand the differences in the glaze firing temperatures so I want to just explain that first of all let's talk about what a pyometra cone is so parametric cones our cones that are formulated of a very specific clay body to bend at a very particular temperature so if I show this one okay where's the camera there we go so as you see this cone it's stamped with a six this is cone six so this is going to bend somewhere in the neighborhood of like 20 to 20 if I remember right so this is my target temperature for my stoneware glazes that I use I use coyote cone six glazes and I fire two cones six now the way that cone work is you put cones that are three different temperatures or you could do four I just didn't have a fourth cone here so typically I do three different temperatures I do a cooler cone the target cone and then a cone that's a little too hot so this is my cone six cone that I I would use when I fired this is cone five so cone five is cooler and cone seven is right here cone seven is hotter I am not using this cone pack on my desk firing though because if you remember I said my bisque firing is cone zero four I don't actually have any cones you are four cones today usually I'm not using the cones during my bisque firing I use the cones during my glaze firing so I'll show you those when they come out later but they will physically like bend it will start just kind of slump like that when when it reaches temperature since bisque firing is the very first firing that our pieces are going through it's getting rid of the chemical water at this point so I want to make sure that the mechanical water has been completely thoroughly dried okay the mechanical water is the water of plasticity that's what makes it wet so you have to make sure that your pieces are bone dry if you are firing a bisque kiln and you have water vapor in your piece maybe it's way down in the core of your piece and you don't even know it's there if you have water vapor and you take it up past the boiling point which is what 212 degrees Fahrenheit if you take it over 212 degrees Fahrenheit that water vapor will turn to steam and explode you know the power behind a steam engine it's the same thing in a kiln if you have water vapor that turns to steam it will blow up your pieces the biggest culprit for firing problems of things blowing up is water vapor air bubbles can is a problem but most of the time I would say it's probably air bubbles that have a little bit of water vapor in it I've had people maybe kids where they they make a hollow form or something and it's a big air bubble and they forget to vent it all a hollow form needs is a single needle tool hole to allow it to vent so if there's any water vapor that's in there it will vent out but I've had things that are pretty dry that and I thought a kid vented it and I'll open up the kiln and it'll be there in two pieces where it just kind of pops apart I think that it's probably the water vapor that's causing it more than anything though now we're doing a little experiment to show so I have some eggs that I have thrown some have holes at least one has a hole and some of them don't have holes so this one is not vented at all it's a hollow egg we're gonna fire that in this kiln and it is bone-dry it's been dry for about a week so we'll we'll see how that comes out if my plan works the way I think it should the water vapors should be able to kind of get through the wall and it'll be dry enough that it should fire without any problem so just remember water vapor huge culprit so when I am firing I have to make sure that my pieces are not sticking up above the edge so as you can see I'm kind of close but I'm probably about a quarter inch away from the edge they're going on up here on the top so these are some of the drape molds that I made this is the tray that I made early on in the quarantine but I want you to notice that I have some stilts on top of it I put some stilts on top of it to act as a weight and that tray does have a foot it's sitting on a foot I don't know if you can see it I sometimes fire weights on top an item if I feel like it might have a tendency to warp and because I have placed this on the top when I probably shouldn't have I decided to go and wait it down now I do want to talk about different types of kilns the operation of it mine is a scut there are many different great manufacturers who kilns this is my second Scott that I've owned personally and I've owned multiple Scott's at school they're very user friendly I also have a couple of Ellen elves at school which I love the element holders are brilliant on them now this one is computerized my original kiln was not computerized it had a kiln sitter with it I will show you the operation of a kiln sitter in just a minute but this is a junior cone this is a cone five junior cone and the idea behind a kiln sitter is it has a rod which is pushing down in the middle of that junior cone and as the cone begins to melt the rod falls automatically we'll turn off the kiln now even with a kiln sitter you should be using a backup timer if you have one on your kiln and you should be using cone packs to visually check and always monitor how long it's taking to fire I I keep a pretty meticulous log of my firings of my kiln so I know how long it's been taking to do a certain firing so when it gets close to the time that I think it should be I know that it should be time for it to turn off if you do not have a computerized kiln you would probably have an older style that has a kiln sitter with it a kiln sitter is a great little device that will help to trigger the kiln off when it reaches temperature now a kiln sitter has a little three-pronged piece on the inside the middle piece moves up and down and that is where you put your you're a little junior cone so as I put the junior cone here okay it sits there in between the the bottom supports and then the top little support is actually kind of pushing down on it now I didn't actually set this out here cuz I was a little camera but out here you can see there's a little weighted I'm just gonna call it a pendulum I don't know what else you would call it there's a little weighted piece right here and this little top thing when that is pushed down it pulls the weight in place now that is being held up the little rod is being held up so let me fix this and I'll show you so I hold up this little rod I slide the junior cone in there and the stamped cone temperature is on the top of it not on the bottom okay and then out here you can see because the rod is above the junior cone now this little trigger is in the up position and it's holding the the pendulum in place when the junior cone bends so this is an example of one that I took out of there when the junior cone bends the top rod is going to fall and Bend this little this little guy right here that's going to raise up okay this will raise up when it falls and bends and then the pendulum part will fall down now the power switch oops pardon my hand the power switch is right here so as I push that in that brings power to the kiln you can see my power button is on currently I have it on off but if I turn it on low you can hear it the relay just kicked on and that is starting to heat up okay now this little baby test kiln is a nice little thing that I use maybe occasionally to test out of glaze if we have a glaze sample we're going to try now the way that I normally would use these especially when I had a larger kiln and I used to fire everything with a cone sitter I would usually start off especially if I'm bisque firing I would take out both of my peephole plugs okay when it was on low and I would crop the lid and when I say when I say profit I would put like a little post in there so it's a up a couple of inches now that's for bisque fire I would do that on low for a couple of hours just to keep it so it can dry out really well then after a couple hours I would drop the lid peep the plug the peep holes if you have an undermount vent you could plug them both if you don't have an undermount vent leave the top one unplugged and then you could maybe two more hours on low once it's dropped then turn it up so every couple of hours then maybe I would turn it up halfway and then eventually to get to the final temperature after two hours there I would turn it up again now you will be testing your kiln and paying attention to how long it fires so you know if it has gone past the time you should be checking it and turning it off and if you use cones a cone pack when you fire it's very helpful so that I am I'm just gonna turn this off right now okay because I'm not really gonna fire and I'll take out my little junior phone and then when that just fell it actually turned it off so when when this pendulum falls you can see that the little power button it pops out and it will automatically turn off so that's how a kiln sitter works hopefully that makes sense but just remember slow steady drying is what you want even though this video is about disk firing it's important to keep in mind Belize temperatures that you'll use eventually you need to make sure that your glaze is compatible with your clay body if you have a low fire clay body you have to have a low fire glaze low fire is usually in the range of cone zero five zero six zero seven depending on what it is mid fire is about comes five and six and then high fire is going to be stoneware and porcelain up in the range of cone ten cone twelve and at that point a lot of people get into reduction of gas firing okay so now I'm ready to go ahead and drop my lid the lid support just holds it in place I happen to have a lid lifter on mine which I probably don't need on such a small kiln but I do like it especially the older I get with my back it's kind of nice now this little lock is just a safety to keep it from being opened I don't really need it but I do use it I have four people's I'm going to leave the top people open bring my vent hood down now I used to have an environment that mounted underneath and actually I still have that pipe sticking out down there I just don't have a working vent anymore I haven't taken it off but I do like this vent a kiln the hood because it removes a lot more of the heat from my space so I don't notice it doesn't like it doesn't heat up my ceiling and my kitchen floor above it quite so much and I also don't notice any fumes now let's talk about how I'm going to turn this on ok so as you can see it is flashing idle right now and it's just flashing the temperature that it currently is I think it might be off by 2 degrees but it's it's pretty close to what it is right down here in my basement that's why it's so chilly right now so normally when I come back here though before I have cleared it out it will flash the completed time and how long it took so like my last firing was completed in 8 hours and 40 minutes and I know that because I haven't written down on my log so the first thing that I want to do is I want to hit stop okay and that clears out anything that's there so if it had the completed time it clears it out now I am doing a bisque firing I do have my choice of two different methods that I could fire so you can see this is what makes cuts very user-friendly it has this cone firing programs which are automatically programmed for either slow medium or fast firing or over here on the right I could do my manual programmed ramp hold mode which I use these quite a bit if I am doing a specialty firing link may be crystalline glazes or glass fusing or maybe I am in a rush to dry something out and I need to dry it out slow and steady I don't like to dry things out that much in my kiln though because the more you hold it at a low temperature those relays come on and off on and off and I just feel like it lessens the life of them so I like to have things bone-dry really as a rule of thumb when I'm firing okay so let's talk about the cone firing program because that's what I'm going to use I the first step is I hit cone fire and then it's asking me do I want to preheat you can see that says preheat zero zero zero I do want to preheat on this it's a bisque firing I need to make sure that that water is out of there so even though I know this is bone-dry I'm going to preheat it for an hour and 30 minutes if it was a little bit thicker and I was a little bit concerned I would preheat it for a longer than that one of the tricks that you can do if you're ever concerned has your water vapour left your pieces when you have that open the top peep peep hole that's open you can hold a mirror right above it and if there's water vaping coming and coming out it'll fog up your mirror or a piece of glass something like that okay now it's asking me the cone so it remembers the last firing that I did which was cone five but this time I'm doing cone zero four because I'm doing bisque so I have to change my cone zero for enter my speed now I have choices of slow medium or fast now slow I would definitely use if I had really big pieces big platters big bowls maybe things that were a little extra thick I would do slow medium was probably what I use the majority of the time and that's what I'm using today I have you know a few like trays I have a few big vases but they're thin I have several cups so this is what I'm going to use now fast would be if I had a bunch of small things very thin I'm not worried about them being fragile I might do that but I do tend to use medium just to make medium or slow sometimes to make sure that all of the water vapor is gone and to help maybe burn out a little bit of impurities that might be in it sometimes if you don't fire quite hot enough on your bisque or slow enough on your best you might get bloating on things either that or maybe you've overfried you glaze and so I'm going to hit medium and then enter now the whole time it's asking me do I want to hold it at the final temperature do I want to hold it at Kohn Oh for I don't typically hold bisque that much but I will just I'm gonna go ahead and hold it at ten minutes quite simply because I'm doing medium instead of slow and then that brings me back to idle and now I hit start you're gonna hear the real a click now when that clicks that indicates it's sending electric there you're gonna hear the real a click on and off a lot during the firing especially in the early stages because it's trying to heat it up and then it holds it it heats it up and then it holds it there if it if it didn't click off it would just continue heating which it will do that closer to the end of the firing cycle when you're reaching the final temperature it will click but not click off right away it's gonna be on and glowing and hold it there for a while okay so I'm looking back at my log and I can see the last time I fired I would I would probably guess the kiln wasn't quite packed as full as this when I have a packed kiln it can take a little longer to fire but I can see my total time was 9 hours and 22 minutes I didn't preheat it for quite as long though I only preheated it for 40 minutes so if I add on 50 minutes to that it'll be I would estimate a little over 10 hours to fire so we're gonna we're gonna set a timer and I'm gonna come back and I'll be checking it periodically oh and also I always monitor a kiln when I'm firing it I make sure that I'm around I am this is in the morning I've started it in the morning and I'll be firing it through the day so I'll be checking it and this will be off before I go to bed tonight the last thing that I want to do and I was waiting until I was done talking is I am going to turn on my vente kill them so it's going to vent the whole time so it's easy it's got a little switch back here if you would like to see how I installed the vented kiln I have a video on that that I did I really like it the unfired vent was nice but I had difficulty with it heating up my studio space too much there for heating up my my ceiling and my kitchen above it got really hot so this helps to eliminate a little bit more of the heat so I'm gonna let that go make sure that I don't have anything combustible I'm gonna move my chair out of here that I was sitting on when I was programming it and we'll check back in a little bit and we'll see how it is from time to time ok my kiln is done firing and it's cooled off now you will see that my time complete is flashing here it says it took 10 hours and 48 minutes which I'm going to mark on my log and that is right in the area where I thought it would be I thought it might be I had estimated somewhere around just short of 10:30 but this is a very full kiln so it probably took a little bit longer [Music] okay so and I did not mention it but it was showing it was 78 degrees I do not open my killed when it's over 200 I like to be able to wait until I can physically touch them with my bare hands I don't like to cause thermal shock or anything so if you recall I had a few eggs without any vent holes that I mentioned I was firing these are completely hollow forms that had no venting and they did not blow up it's because they were dry so just remember that it's not air that makes something blow up it is water vapor there my spoon rest weeks ago here are my tiny little dishes that I made for our our little Hedgehog I need to glaze those because she's been needing those for some time and this and this these are drape molds I made so I can drink clothes where I'll do some more videos with those and I know I mentioned it before but the reason I put these on my finished tray there was to help prevent warping I did dry it a little faster I had a little bit of working so that helps to flatten it out some these are some molds that I have made for a video that I'm going to shoot there's the square plate with the slip trailing some more deep molds here's my little salt-cellars that I made that was one of my early coronavirus videos here's my citrus juicer and the couple of vases this was the vase that I did when it had the red gouache paint on it and noticed the red is gone this is what I was said I said would burn off the other vase the these are going to be luminaries that's what they have the holes my little Faberge inspired egg my shaker my cups with the spirals and then I have a whole bunch of my I didn't do these with videos I have a whole bunch of my National Parks mugs mishima cups I I did show I shot a video of this but I haven't I haven't done anything with that video yet so I'll show you the interior of the kiln right now so you can still see I have another shelf in there that I need to take out what I really wanted to show you was right here where the thermocouple sticks out this is the temperature gauge the temperature sense sensor I wanted you to notice what was underneath there the thermocouple does flake from time to time during firing it just oxidizes and things flake off of it I have been meaning to make just like a little kind of cover to go around it which I think I might just to help corral that stuff so it doesn't flake all over the kiln it may potentially get on pots even though so I hope you all were able to pick up something from this if you don't have experience firing kilns hopefully this will help guide you a little bit to give you a little bit more confidence so don't forget to Like and subscribe comment and share it with others if you think anyone can benefit from it so stay safe stay healthy and keep potting if you can [Music] you [Music]

Channel: KaransPotsAndGlass

Views: 27,693

Rating: 4.977169 out of 5

Keywords: Beginner, Novice, easy, simple, learning, show, how, learn, teach, demo, demonstration, tutorial, showing, Fire, Firing, firing, program, cone, thermocouple, pyrometric, cones, 04, bisque, vitrify, water, dry, vapor, bubbles, steam, explode, correct, understand, understanding, programming, preheat, glaze, best, video, beginners, for, youtube, channel, pottery, potter, clay, ceramic, ceramics, high school, teacher, class, classes, explain, explaining, teaching, teaches, student, students, advanced, intermediate, technical, advice, Karan, Witham, biscuit

Id: LjsKTEQX3lg

Length: 32min 32sec (1952 seconds)

Published: Sun Apr 26 2020