Jeryko

Hey Ollie. Just completed the build. Turned out better than expected. Only issue is that I did end up using more amps than I previously thought to get it to temperature fast enough. I'll write the specs if ur curious. 
Thanks everyone else for the feedback and great ideas. Rpi controller rocks by the way :). 
@Sorcery holly cow. Glad to see you here dude. Haven't had time for The Nut in quite a while. 
 
The end product:

Hey Ollie. Just completed the build. Turned out better than expected. Only issue is that I did end up using more amps than I previously thought to get it to temperature fast enough. I'll write the specs if ur curious. 
Thanks everyone else for the feedback and great ideas. Rpi controller rocks by the way :). 
@Sorcery holly cow. Glad to see you here dude. Haven't had time for The Nut in quite a while. 
 
The end product:

Hello everyone,
I've started dabbling in pottery about three years ago, making bonsai pots. This fits with another hobby of mine, you can guess which  :).
Point is, after firing my works with some acquaintances, I've decided that my own kiln is a must in order to really progress in the craft. The problem is that I my backwater location the chances of buying a second hand one are next to none, and I can't really justify spending almost $2500 for a new one. So I came up with the idea of actually building one from scratch. Yes, I know it's hard, yes, I know it can be dangerous but I'm trying to be as smart about it as I can and mitigate all the risks as much as I can. 
I would really appreciate it if you ladies and gentlemen would be willing to part with some knowledge to help me have the best possible outcome for this project. 
Now for the tech specs:
In order to fit the nature of my work, I would need a 50x40x30cm interior.  (19.7x15.7x12 inches)
The temps needed would be around 1240°C (2264°F)
The power I can get away with as a household consumer in my location is 230V 16A ~ 3600W
This takes me to my first point: As far as internet wisdom goes, the Wattage needed for a pottery kiln is 0.6W/cm2  which would place me at a needed Wattage of around 5600W. Waaaay above what I can provide. But then I read specs for kilns produced on Germany like Nabertherm that for a 60L pottery kiln with a top temperature of 1300°C produce single phase 230V 16A models, which makes me believe I can do it.  I'm assuming that I'll need to go with more insulation and longer firing times, but it's doable. Is that accurate?
Next up, elements: luckily I have a provider for Kanthal A1 wire near me and prices are decent. Would 1.6mm  1380°C max,  0,721 Ohm/m be suitable? With this diameter I seem to be able to juggle the resistance, wattage, length and placement of elements as close to optimal, with 2 elements running in parallel. 
Thirdly the most amusing topic... Well not amusing but maybe the most complex. The controller. 
Being in IT i'm a sucker for gadgets. Usually buying them, true, but this time I'm thinking about building :). I saw a lot of projects on the web with Raspberry Pi kiln controllers. The features they provide, the adaptability and the connectivity of the systems sounds amazing. Question is: does anyone fire with something like this? How does it compare to commercial controllers that are super expensive and in the stone age as far as features go. Are they worth the trouble? An example project that stuck with me is below. But there are many more
 
Thanks for the help, and looking forward to chatting with you.
Mihai

Hello Liam. 
The 16Amps : Couple of reasons. First and foremost, modern contractors in Romania are cheap idiots. The ones that built the house I live in at least...  I have a 3x2.5mm copper wire cable going from a 20A breaker (easy to replace) to my detached basement (completely disconnected from the house, next to it below ground level rather than under) . According to code, the cable is rated for 20A when enclosed, 32A in the open... So 20 in my case. 
Secondly, single phase wall sockets are all rated 16A in RO.  If i hardwire I can go past 16 but with safety margins on the current cable I wouldn't really want to do that. The other option would be to replace the cable with thicker gage, but that involves an electrician and if the tubes inside the walls are not done properly and the old cable can't be used to pull in the new one, it might cost a small fortune.  
The basement situation above explains why I'm not overly concerned with fire. The whole thing is concrete below ground, detached from the house. If any mishap should happen worst thing that can burn are four car tyres and two stools :)). 

Heyya @Hulk. Thanks for the answer. I would love a gas fired kiln. The concept scares me a bit, but would love one. Only issue there is with management (please read the Mrs ) . She agreed to an electric one but will probably divorce me if I make what she calls 'an improvised bomb' in the backyard. Except for that, she's pretty cool :)). 
Totally get the equipment buying. I do the same for all my hobbies and then milk them for all they're worth :). 
The 2cubic ft is probably the max size for which I could squeeze out sufficient Wattage from my electric system. I'm limited to 230V and 16A. So it's gotta be electric and it's gotta be small. Good part is that I only do it for a hobby and occasionally take on a pot commission but the size should be enoughish. 
About the controller, looked through 30 pages of this forum, and a whole lot of internet. I found a couple of interesting ideas and implementations. Was wondering if I can get a little more first hand feedback as to how they behave. Most of the threads are a couple of yeas old and look quite dead. 
Hello @CactusPots. Thanks for the reply. I actually found shelves that fit my proposed kiln size :D. So i'm hoping to be able to stick to it. Did the math already, so it's just that I need confirmation about whether the power is enough or not and if the wire gage is suitable.  I'd kill for a discussion with someone who owns a Nabertherm Ecotop 60. That's the one that has 60L with only 3.6kW. There aren't really any speciffics about the model on the internet except for some basic stats. 
 

Heyya @Hulk. Thanks for the answer. I would love a gas fired kiln. The concept scares me a bit, but would love one. Only issue there is with management (please read the Mrs ) . She agreed to an electric one but will probably divorce me if I make what she calls 'an improvised bomb' in the backyard. Except for that, she's pretty cool :)). 
Totally get the equipment buying. I do the same for all my hobbies and then milk them for all they're worth :). 
The 2cubic ft is probably the max size for which I could squeeze out sufficient Wattage from my electric system. I'm limited to 230V and 16A. So it's gotta be electric and it's gotta be small. Good part is that I only do it for a hobby and occasionally take on a pot commission but the size should be enoughish. 
About the controller, looked through 30 pages of this forum, and a whole lot of internet. I found a couple of interesting ideas and implementations. Was wondering if I can get a little more first hand feedback as to how they behave. Most of the threads are a couple of yeas old and look quite dead. 
Hello @CactusPots. Thanks for the reply. I actually found shelves that fit my proposed kiln size :D. So i'm hoping to be able to stick to it. Did the math already, so it's just that I need confirmation about whether the power is enough or not and if the wire gage is suitable.  I'd kill for a discussion with someone who owns a Nabertherm Ecotop 60. That's the one that has 60L with only 3.6kW. There aren't really any speciffics about the model on the internet except for some basic stats. 
 

Hello Liam. 
The 16Amps : Couple of reasons. First and foremost, modern contractors in Romania are cheap idiots. The ones that built the house I live in at least...  I have a 3x2.5mm copper wire cable going from a 20A breaker (easy to replace) to my detached basement (completely disconnected from the house, next to it below ground level rather than under) . According to code, the cable is rated for 20A when enclosed, 32A in the open... So 20 in my case. 
Secondly, single phase wall sockets are all rated 16A in RO.  If i hardwire I can go past 16 but with safety margins on the current cable I wouldn't really want to do that. The other option would be to replace the cable with thicker gage, but that involves an electrician and if the tubes inside the walls are not done properly and the old cable can't be used to pull in the new one, it might cost a small fortune.  
The basement situation above explains why I'm not overly concerned with fire. The whole thing is concrete below ground, detached from the house. If any mishap should happen worst thing that can burn are four car tyres and two stools :)).