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Showing results for tags 'Gas'.
Found 20 results
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Hi all! I just finished converting an old electric kiln to gas. The firing will be totally manual, no kiln sitter involved. Having never fired a gas kiln, I know my learning curve will be steep! But I need a few pointers to get started. I want to start out with a glaze firing, ^5, mainly because I don’t have any greenware to bisque right now. I have a few “sacrificial pieces” that I am willing to use to start the learning process. I have a pyrometer and witness cones ready to go. So, my main question has to do with ramping at this point. How fast do I want the kiln to increase in temperature on the way up to ^5? The pieces I have are made from Laguna 52 Buff, and glazed with Spectrum underglaze and/or Spectrum ^5 glaze. Idk if that makes a difference, or not. I am a wheel thrower, and I typically throw thin. Don’t know if that matters, or not, either! I realize that glaze firing in particular can vary based on the desired effect, but I’m looking for a basic framework to start from. Based on my small test fire (only brought the kiln up to about 900-1000*, empty, to decide if I need one burner or two) my biggest fear is that the temperature will rise too quickly, and the heat stress will cause issues-up to and including cracking/exploding. Thanks! Amy
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Since day 1 I wanted to do wood firing. I started with an electric kiln and although it is possible to do interesting things I'm still focused on ultimately doing Anagama. I cant truly test Cone 10 glazes in my electric and want to get as close to possible to that environment, which means a way to do reduction, neutral and oxidation. So I got a broke down Duncan kiln donated to me and the burner came in today so I'm super excited!!! Stripping it down tonight and getting the elements out then will figure out how to cut the burner port and the top opening. Then I have to find a 40 - 50 gallon tank. Gaaaaaaah excited! df
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Hi, I currently do smoke firings in an oil drum, fired with wood, but I would like more control over the temperatures reached. I’m thinking of building raku kiln from another drum and trying saggar firings. One question I have is about regulators. I had always intended to use a high pressure regulator but have found it difficult to source an inexpensive change over regulator (I want to be able to connect two gas bottles up) for high pressure systems. There seem to be plenty of change over regulators for low pressure systems, so I was wondering if it would make any difference if I went for a low pressure system instead. I believe some people use low pressure systems for raku. What are the differences between using high and low pressure systems? Is there a difference in the results, the time it takes and the cost? Also, how many firings would you expect to get from a 5gk or 10kg gas bottle? Thanks Kirakat
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I know this kind of thread has been done many times. I've read lots of them, watched lots of YouTube videos and clayart topics. From this I have learnt there are many problems with this kind of conversion. I have never fired with gas, but I love the look of reduction glazes and my old electric kiln was nearly dead anyway. Following a recent house move I faced the prospect of a costly electrician bill to install it in our outbuilding, and decided that converting it to gas would be comparable in cost. Initially I was going to do an updraft kiln. After reading many uneven firing woes I decided the cost and hassle of building a chimney would be worthwhile. I decided to spend a decent amount of money on a burner. I know one burner kilns aren't as good as 2 but I don't have money for another one. Mine will fire up to a 10 cubic ft kiln apparently. It has flame failure protection and a needle valve so it should be ok to fire my small kiln hopefully. My kiln is 17" width and 22" deep so around 3 cubic ft. So burner is overkill but perhaps I will build a bigger kiln from scratch in the future and I don't want to have to buy more burners. After ordering the burner I read this thread which is very close to what I intend to do. Joel originally had a very similar burner to mine, although his was 90 degree and mine is straight. I'm worried that this doesn't bode well for my success as he totally changed burner setup after failing to reach temp. I do think there might be something in the comments about his chimney size though... So I'm going to press on with a larger chimney. I'm hopefully goes to collect some 230x114x76mm insulation bricks next week. I have worked out on paper my chimney setup. Things I need to decide now: 1. Do I use 50/50 fireclay and grog mix with some sodium silicate or something else like expensive kiln mortar to stick bricks together. 2. Burner port placement. There isn't going to be much room at the base of kiln with that chimney opening. Can I have a burner port above the floor shelf? I guess pots directly in flame path would get too hot. 3. Connecting chimney to kiln opening. This needs to be insulated, so do I use like a 2cm thick strip of kiln brick as a kind of bridge all around the 4 planes of the connection. This would reduce the area of flue but would be worth it? Not sure if that will make sense to anyone? I could ramble all day about this, I will probably just keep posting my progress and hopefully someone may be able to help me out of the darkness and into the light! Edit: the 114 in image should read 76!
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I need to find the best All-In-One clay for cone 5, great for both hand building and wheel throwing I know. That's a tall order. But I can dream. I have a pug mill and don't want 2 bodies. Problem: I have too many problems with my gas kiln for cone 06 anymore. I'm DONE. I am moving to cone 5. Criteria / Factors: I'm in Southern California I teach 180 high school students grades 9-12, all levels of art skills, so it has to take punishment Not too sandy on the wheel, not too smooth or squishy for hand building Not too dense so it is so top-heavy when trimming I'm willing to pug the new clay to soften it for throwing, if it is stiff and great for hand building, or visa versa Doesn't stain clothes or the tables, rolling pins, or make a mess everywhere Is not pure white (students can't see where they missed glazing spots when using light color glazes - painting) Good leather hard, doesn't soften up too easily when re-wetting to score things together Doesn't take every indentation to the surface of pieces, temperamentalD Centers on the wheel fairly easily, especially for teen girls with tiny hands Can take a good amount of water from beginners Pulling walls, it is strong, doesn't warp or sag easily Won't dry out too quickly in hands while hand building Doesn't bend or warp easily when removing from the wheel Not so soft that it caves when cutting and sliding off the wheel Doesn't make teens hate the class because it stains clothes or gets everywhere and of course, takes glazes well and can handle a little fluctuation in gas environments Cone 5 clays I've Tried: Laguna - Dover White: Nice clay, but pure white. easy to center, but A little soft when hand building Laguna - Plain (Buff): Nice light tan color, easy center and to rehydrate if repairing, but a bit too squishy and shows every dent Laguna - Moroccan Sand: I love this clay, doesn't leave residue - color, but a bit dense to center. It is really dark grayish brown, if they only could lighten it Laguna - Buff with Sand: Nice tan color, but WAY too sandy for students on the wheel Laguna - Greystone: Too dense and top heavy for small pieces, hard to center, but really takes a beating with water, warps when thin due to density of surrounding clay Laguna - Speckled Buff: A bit dark in color, has iron so it gets read everywhere, could stain (think girls with pure white vans) Laguna - LB-6: hmmm, can't remember, but nixed it very soon after Laguna - Sante Fe: OMG - red EVERYWHERE, like a crime scene Aardvark Clay - SBF - Too dark tan - a bit sticky for students Aardvark Clay -Arctic White: Too white Opinions???? Go!!! -
Hi everyone, I recently fired a gas kiln but there was very poor reduction and my pieces (with a celadon glaze) came out oxidised. Would it work to refire these same pieces in a fully-functioning gas kiln? Is there any reason the might not reduce as they have already been high-fired? Thank you!
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I’m a recent grad working on setting up a studio space on a really tight budget, and my current plan is to convert an old electric kiln I got for free into a propane-fueled gas kiln. My original plan was to fire it with a pair of propane weed burners, (like simon leach’s conversion) but it’s occurred to me that could be a safety issue during an overnight preheat. I’m planning to once-fire most of my work to cone 10 reduction, and I’m used to the university gas kilns, which use Venturi burners with pilot lights and safety shut offs. My usual firing schedule is an 8-10 hour overnight preheat, bring it up to cone 06 slowly (4-5+ hours, reducing 012-09) and then up to 10 quickly(1-2+ hours) and letting it cool naturally. Obviously I’ll be monitoring the kiln while it’s firing, but I’m worried about the preheat. On the other hand, I don’t have a ton of money laying around until I can start firing work to sell, and proper kiln/forge/raku burners are prohibitively(for now)expensive. Does anyone have any advice for this? Maybe an inexpensive burner actually designed for long-term use? Or an alternative firing schedule that doesn’t call for me to be awake and alert for 16-24 hours?
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Hey y'all -- So I have an old Jenken sitter kiln I got from a retired potter (along with my other equipment). Earlier this year I converted to fire with gas (downdraft), using a homemade cast-iron burner with a squirrel-cage fan. I don't have any issues getting it up to temperature, but I have noticed that it is significantly cooler closer to the bottom of the kiln, and it feels like an unacceptable portion of my work is not getting the heatwork it needs. I don't load anything on the floor of the kiln, but have some bricks to help steer the heat. I've tried a couple configurations, but every time I fire there are very significant differences across the strata of the kiln. I'm pretty frustrated and can use some guidance. Some details The burner sits underneath the kiln and fires upward into the kiln, close to its edge. There is an external chimney made of soft firebrick. The flame enters the chimney through a port on the side of the kiln, which is on the other side from the flame's entry, floor-level. I've cut a little bit off of the shelves I'm using to allow for the heat to move unimpeded. I'm not an expert by any means -- my initial thoughts are that the heat is moving past the first shelf too quickly, or has no reason to linger there. I'm considering placing the second shelf offset, so as to block the flame and persuading it to move around toward the top of the kiln, sort of like a spiral. I'm concerned about possible crackage, though, or any issues I might not be foreseeing. Just curious about any thoughts that y'all might have. I understand that gas kiln conversion problems are probably tricky to diagnose, but I'm wondering if there's something elementary I could try that I've overlooked, or some kind of general troubleshooting checklist for those of you who have more experience tinkering with this method than I do. thanks! Kevin -
I have decided to take the leap and build my own studio. I want to put in a front load gas kiln and would like input. I searched the forums and unless I missed it, I couldn't find much on gas kilns, so forgive me if this topic has already been addressed. I have been looking at the Olympic DD12 and the Bailey Front Load Standard 18/12 and I have also talked to Seattle Pottery about their Crucible front load kiln. The Bailey is about twice the price of the Olympic and the Crucible. My plan is to have an attached shed on the studio in which to put the kiln. I live in Montana so it will need to be protected from the weather. I figured it would be better to decide on the kiln so I can know what size to make the shed - area and ceiling height. I would appreciate any thoughts, experiences and ideas. Thanks.
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I am rebuilding an AIM Gas Kiln model 2327G (About the size of a Skutt KM1027). I'm looking for help in finding a operating manual or copy of original instructions. I called Aim and they don't have instructions for the older gas kilns anymore. I'm interested in if there were baffles originally at the bottom of the kiln to redirect the flame. It has 3 Gaco 75,000 BTU burners and is set up for Natural Gas. It's about 20 feet from my Gas meter on a 3/4" line. Any input or help would be appreciated. I intend to fire at Cone 10 reduction.
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Good Afternoon, I'm using a Paragon HT22 kiln with the Dwyer gas inlet flow meter. I'm producing small wire springs (stainless steel) that need to be heat treated in order to secure their final form. In my regular smaller kiln, the oxygen in the atmosphere is reacting with the heated stainless steel and results in pretty intense discoloration (brown/dark purple/etc). Using my new kiln with a tank of Nitrogen gas hooked up, I am able to produce springs that have only a slight blue discoloration. This drastic reduction in discoloration/oxidation means that the nitrogen gas is working it's magic, and pushing the vast majority of oxygen out of the kiln, creating an ALMOST perfect inert atmosphere. The question is: IS IT PHYSICALLY POSSIBLE to create a perfectly inert atmosphere in the kiln? Is there something I'm not seeing here? I'm investigating trying to get a higher flow dwyer meter to allow me to pump nitrogen in at a higher rate, but in my gut, I feel like it's not possible. The removal of this blue oxidation requires a chemical bath, which is certainly within my ability to perform, but I'd really rather not. Does anyone have any experience with these gas injected paragon kilns? Any words of wisdom/tips/tricks? Appreciate the help. Kiln on. -
From the album: Gas Kiln
Turning on the gas -
I am struggling to control the heat rise of my gas downdraft - it gets too hot too quickly! I'm test firing empty (I've put in all the kiln shelves) to learn how to control temperature. I'm trying to emulate a slow bisque as I will be firing large, thick sculptural pieces. I'd like to control heat rise to 20 - 30 deg. C per hour, particularly for the first 100 deg. The slowest I've managed is 200 deg. C in 30 minutes! This is with one burner lit, at it's very lowest setting (the flame is JUST clearing the port inside). The top of the kiln heats really quickly and after 30 mins., the top kiln shelves are too hot to touch, but the bottom shelf / false floor is just comfortably warm. I've tried different damper settings to no avail. I'm thinking that there is insufficient draw to pull heat down throughout the chamber. And maybe that my burners are just too powerful for a slow bisque? My next thought is to heat the stack somehow - maybe put a blowtorch in the damper slot to heat the flue air and create some draw. And/or look for a smaller burner that I can use for early stage heating (something like a domestic gas burner that can run at a lower flame/heat setting). I'd REALLY appreciate any feedback/suggestions anyone can offer. Thanks! P.S. It's a converted electric, approx. 8.5 cubic feet. Flue area is 6x6 inches narrowing to a 6 inch diam. pipe. The kiln is fired by 2 venturi burners, using LPG (propane), and the flue outlet matches the area of the burner inlets (as per Olsen).
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Hello everyone, I am new to this form, and new to kilns. last week i started trying to make an updraft gas kiln, and it seems i hit a wall that i need some help with. Setup : Kiln inside size : 9" x 18" height 15" first shelf @ 6" Bricks used : Firebricks/ refractory bricks 9x2.5x4.5 ** Dry stacked ** Gas : LP Temperature : K type thermocouple sensor (0-1300 c ) positioned at 9" height on the sidewall and sticking out 1.25" (https://www.amazon.com/gp/product/B00UWVZAY8/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1) The problem : I cannot get the kiln to go more than 1200 degrees Trials : 1- With heat source positioned flush with inside wall, two top bricks open. Temperature rises to 500 f within 5 minutes and then within 10 minutes to 600 degrees. From then on temperature will stay between 600-700 degrees even after 45 minutes. adjusting the gas flow at times helps get it to temperature. 2- Continuation of 1 : top bricks closed... temperature drops fast to 400 degrees and with adjusting the gas down to accomodate less oxygin i can bring it back up to 600-650 3- Same as 1 but after 30 minutes i started opening up holes in the bricks by sliding them apart without burning myself to make more air holes... the more holes i open the higher the temperature got.... reached max 1200 f 4- same as 1 with burner positioned 2" outside of the Kiln. same max temp as 1 From what i am seeing and from the amount of carbon in the kiln after so few firings, i think i have too little oxygen in the kiln. It is my first attempt to make a kiln and from all the pictures and videos i saw i didnt see holes in an upward drift gas kiln, other than the peek holes, which i tried to make but it only increased the temperature upto 900 f. Do i have to make holes all over the kiln for oxygen? is the kiln design just wrong? is it too small ? i really cannot figure out what is the next step i should try, or just redo the whole thing with a different design. ANy help is very much appreciated. Here are some pictures of the project. Thanks in advance, Layth -
I recently paid off my student loans and bought a house so I decided to dig my ceramic equipment out of storage where it has been for the last 15 years. While doing schooling and an internship in ceramics I bought a second hand little Amaco Gas Kiln Model # AG40 Serial# 192 . I loved this kiln because we did many raku firings with it at the pottery and I would love to repair it and fire it up again now that I have space. The issue is that I can not find any information on the kiln and I am also in the process of cleaning up and repairing the burner. I was wondering if any here heard of this kiln and maybe know where I could get parts, new or used, or even an instruction manual. Thanks! Al
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From the album: Gas kiln 2013.09.05
gas kiln, reduction , cone 10 -
From the album: Gas kiln 2013.09.05
gas kiln, reduction , cone 10 -
From the album: Gas kiln 2013.09.05
gas kiln, reduction , cone 10 -
From the album: Gas kiln 2013.09.05
gas kiln, reduction , cone 10 -
I have found several pages that all repeat the same: OK, fine by me Lets say we have a 250 l kiln (9 cf). We are going to need 16000 x 9= 144000 BTU We know that 1 Kg of propane packs about 13.97 kWh or 47668 BTU So, 144000/47668= 3.02 Kg (6.65 lbs) of propane per firing to cone 10? (I am using weight and not the volume because volume can be anything if exact pressure and temperature are unknown) Q 1: How close is this to actual gas usage? About the downdraft kilns and actual stacking area. Q 2: Is it safe to say that 250 l total inside volume will give us only about 155 l of stack space? I am asking, because we like to make some firing cost calculations before we start taking bids for building a 250 l kiln... or do we actually need a 350+ l kiln Thank you.
