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Hi all, I'm planning on building a hobby kiln for my partner, and am in the process of choosing refractory materials and kanthal wire for the heating element. Was hoping I could get some advice from anybody who knows about these things. I want the kiln to be light weight and very efficient. I'd like to use ceramic fibre board as an inner layer of insulation (rated to 1400 C / 2550 F), and calcium silicate board as a secondary layer (rated to 1000 C / 1830 F). The ceramic fibre board is very expensive compared to the calcium silicate board, but i can't only use the calcium silicate board as it's only rated to 1000 C / 1830 F. So my idea is to cement the two boards together, with the calcium silicate board on the outside, so that it won't exceed 1000 C / 1830 F. I'm wondering how thick the ceramic fibre board needs to be such that the calcium silicate doesn't reach that temperature. We'll be firing the kiln to about 1280 C / 2340 F. My other question is about kanthal wire for the heating elements. I'm wondering what gauge of wire I need. The kiln will be about 40 litres / 1.3 cubic feet. I want it to get up to 1280 C / 2340 F. Based on similar designs that I've seen online, it looks like I'd need it run at about 3600 watts. I'm wondering what gauge kanthal wire I should use for a well-insulated kiln that meets these specs. If anyone has any idea about either of these questions I'd really appreciate your thoughts! P.S. I'm aware of the health risks of working with fibreboard, and will be using the proper PPE and precautions.

I guess I want to try it. Any sugestions and any good sources on how to do this out there . Don't want to read a book, a simple how to is what I'm looking for. What size wire do they have. Any ideas are welcome.

Hello everyone, I’m a newbie here, my first post. I’m trying to find out how to make fully glazed spoons/salad servers. The best solution I can find at the moment are some stilts with metal pins from Scarva. Hopefully they would just leave small pinprick marks in glaze? I’m handbuilding in stoneware clay, planning to fire to 1240C. I’ve noticed that many spoons have been made with holes for hanging, but I gather that niochrome wire (sp?) would slump, under the weight? if I can’t find a solution for glazing fully I guess I’ll just glaze the spoons partially. Most of them I’ve inlaid slip patterns partially. Thanks for reading my query.

Hi all I make glass beads and also make pottery. For the glass bead making we use stainless steel rods coated with bead release when forming the beads with a torch. What I am wondering is-- if I coat the steel rods with bead release can I use them for firing beads in a cone 6 electric kiln? I see that people talk about using Kathal wire but I am wanting something that will be thicker and bend less. Any advice you can give regarding glazing beads in cone 6 environment would be welcome. Cheers, Amy

Hello! I hope someone with more experience out there can help me! I am making a wall hanging piece that is essentially a collage of flowers within a round frame, probably around 18 by 24 inches. I am in need of advice on the logistics of this project. I am unsure if it would be more effective to make a large slab and attach the flowers to it before firing (this option scares me!) or if I should divide the overall piece into 4 quadrants and arrange the flowers so when the pieces are put together on the wall- you cant see the seam. The other approach I was thinking of would be making individual flowers, firing them and then adhering them to a wooden backing. Lots of options and things to think about. I will be using cone 5-6 Leguna Frost Porcelain. I attached a photo shopped image for reference.. Thanks! Audrey

I use nichrome wire hooks to hang decorations no larger than half the size of the palm of your hand and no thicker than 5mm, though often a lot smaller and a lot thinner. I've been using hooks as the decorations are fairly heavy and so I use thick bead rods - too thick to thread directly through the holes made in the clay. (If anybody could suggest a better method I'm open to making my life easier, bending 100 pieces of wire and hanging takes a lifetime!) The wire itself is sturdy and doesn't slump, however I use a white stoneware body, decorated and transparently glazed. After a stoneware glaze firing (I glaze to 1250) I have what I can only describe as green burn marks above the area where I've cut the hole, right where the wire sits, though the wire does not touch the piece. I thought it might be the wire getting old, it can become quite black and brittle after several firings. However after replacing it with new wire I have the same problem on the first firing. I can't remember it being a problem I've always had, and I've tried several different clays recently in a sampling run - it's happened with all of them, so just trying to rule things out. It's ruining what would otherwise be completely saleable work and I'm totally confused! I really hope I'm missing something obvious here; can anybody shed some light please!?

Hello all! I believe I've already post about this one project I've done, but now I have a whole new question about it. While I was sculpting these hands, I slipped some aluminum alloy armature wire inside the fingers and never took it out. I was hoping to fire and glaze them, but I'm worried that it will explode because of the armature. Should I bother to fire it (someone wants to buy them) or should I just spray paint it and call it a day? Clay: White Stone Mountain Clay (water), 8" long, widest part is 1 1/2" I was told by the man that sold me the wire I could fire the armature, but I'm having doubts. The fingers did crack a little where the wire may be, but the product's website said "The wire will not corrode or stain, and has a melting point of 1220 degrees F/660 degrees C." Thank you so much!! Savannah

I have a porcelain that's not a "true" porcelain because it only needs to fire to cone 6. I don't have a kiln so I can't practice things. I want to make a surface with a few 1" spikes sticking straight up or leaning a little and I was wondering the best way to do it. When I did "poured ceramics" years ago the instructor would use "prop" on the porcelain piece to keep them in shape, but this shop owner doesn't do that because he doesn't fire porcelain (but I think he would if it only went to cone 6) Can clay and porcelain be mixed in the same firing? I had an idea about making the spikes. Rather than rolling them and hoping they wouldn't fall, I was thinking of using a piece of wire and dip it into slip repeatedly (drying between coats) until it got the right size. This is how they made candles in the "Little House on the Prairie" days (only using cording). And if I were to use wire, what guage would I need? 14 guage which is fairly substantial and will hold it's shape or 20 guage which is thinner but would make better spikes? Has anyone had any kind of experience working with wire in "porcelain" or clay?

Hello, I am still having big problems with the kiln I own. Long story short, it has been broken now for about 2-3 months. First off one of the relays fried itself. So I replace that. Then it fired twice, one bisque and a cone 9-10 glaze. After that it broke again with the controller spitting out an Error F1. No manuals or manufacturers known for either the kiln or programer. Looked again at the wiring and the wire attached to the top relay has fried, half of the coating had burnt off and it was getting very hot. This is probably what broke the relay in the first place but I didn't notice. It is on the wire where the electricity exits the elements. The top circuit has 6 elements wired in parallel pairs. Replaced the wire and it was still getting very hot. This time where the elements come out the kiln it was starting to glow and spark which I had never noticed before. So it is not the relay or the wire that is causing the problem it must be the elements right? The problem is I know little about electronics and the guy who I share the studio with knows even less. He had an electrician come over to look at the kiln. Problem was I wasn't there and he doesn't really know what the electrician has done. I am sure he is good at his job but I have no idea what he has done with the wiring. I mean it looks like he has changed the bottom into a series circuit and the top, well I have no idea how it is meant to work. Here is my attempt at working out how he has wired the top elements, to me this makes no sense but please correct me if I am wrong. They are two drawing of the same circuit. I spent most of yesterday trying to work out and design a circuit that will work. The elements look ok to me but maybe they are causing the problem. I just don't know. I know one guy who fixes kilns and replaces elements but he is very slow at getting round to doing anything I took some amp and resistance readings from the kiln to try and work out what the overall resistance is. The kiln consists of two relays, the bottom one has four elements wired in parallel pairs and the top 6. 10 elements in total. Is this the right way to have it wired up? The power comes in bottom left and right and out the middle pins. So I started with what the ideal circuit should be. I have 240v supply at 32amp, which means my overall resistance should be 7.5ohm. Overall the top elements have resistance of 11.6 and the bottom elements a resistance of 10 (one top element has 17ohm and one bottom elements has 10ohm). This makes the overall resistance of the circuit 5.4ohm as the elements are wired up in parallel. Ok so that is the resistance for the circuit but just taking in elements resistance values so probably not that correct. If I use the amp reading that I am getting going to and from the relays I end up with a value of 7.07ohm for the overall resistance which is a lot closer to my ideal value. After all of that I am not really any closer. The top relay has an amp reading of 18.5 and the bottom relay 15.5. I think I worked out that if my ideal resistance was 7.5 then I should have an amp reading of 18.75 for the top and 12.5 for the bottom. I am a bit confused on reading back my working out now haha. I have just noticed that 18.5+15.5 = 34 but I am sure we have a 32amp breaker which doesn't make any sense either. So none of the values seem that wrong although I may have completely done the maths wrong, I mean the bottom seems to have too many amps but it is not the bottom that is broken. Those elements seem to be working fine. The top where the electricity exits the elements to go to the relay is where the problem is happening. Anyway if you have read this far, thank you I don't know if anybody can help but could you at least tell me if the parallel pairs is the correct way for elements to be wired up? Can anybody spot where the fault may lie? I don't want to replace the elements if that is not going to help either! I have just been slowly replacing and breaking more things.