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Hi all,

I've been working with ceramics for a few years, but always at studios where all the glazes are mixed and my work is fired for me. And they've all been cone 10 gas reduction. I've just ordered a kiln (skutt KM-1027 Kiln 208V 1P w FK) and am looking for more information on firing the electric kiln to cone 10. From what i understand it wears out the elements quite quickly and uses a lot more electricity? This makes sense, but it also it seems like there's not a lot of glaze choices for cone 10 oxidation fire? I will probably switch to cone 6 at some point, but for now i still have a bunch of cone 10 clay and work drying so the first couple of fires may need to be to cone 10. If anyone can offer advice - pitfalls/ possibilities of firing to cone 10 in an electric kiln? Which glazes can i use? Any advice/ encouragement would be appreciated!

Thanks in advance,

Nic

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1 hour ago, nic moore said:

but it also it seems like there's not a lot of glaze choices for cone 10 oxidation fire?

A quick search on Glazy brought up quite a few ^10 oxidation glazes. I kept the search parameters at Cone 10 and oxidation but it's somewhere to start.

1 hour ago, nic moore said:

From what i understand it wears out the elements quite quickly and uses a lot more electricity?

The hotter you go the faster the elements wear out. From the Kanthal Handbook on Euclids:

"The following guide has been provided by one wire manufacturer (Kanthal) to illustrate the effect of operating temperature (the figures are for wire temperature; kiln temperature will be approx. 28oC/50oF lower)" (they got the C and F reversed) 

1993901389_ScreenShot2019-09-30at10_58_33AM.png.d45c4fe2bad4bb245a81770e32a75cf1.png

It's super important to really condition the elements thoroughly, especially if you are high firing. Kanthal recommends a longer conditioning firing than what some kiln manufacturers use. From the same pdf as the chart above:  

"From the Kanthal Handbook, referring to their FeCrAl alloys (i.e. A-1 alloy): Conditioning "The durability of resistance alloys in air at high temperatures is greatly increased by an oxide surface layer formed by a reaction with the oxygen of the air. The protective nature of this oxide layer is proportional to its area and depth. Foreign matter usually interferes with the formation of the oxide layer, and this causes a reduced life. ... At high temperatures the protective layer of Kanthal materials consists almost entirely of aluminum oxide. This has a light grey colour and good chemical resistance. At temperatures below 1000oC (1832oF) the oxide layer has a dark colour since the aluminum oxide is impure." 10 In order to protect elements from the effects of harsh environments, it is very desirable to condition the elements, by pre-oxidizing them. This is accomplished by firing them to a temperature of 1050oC/1922oF and soaking for several hours, 7-10 if possible. The process is enhanced by allowing good air flow into the kiln - leave the peepholes open, or the KilnVent on. If you are doing reduction firings in an electric kiln it is desirable to periodically re-oxidize the elements, for best life expectancy. This is not recommended if normal use will not exceed 1050oC (1922oF), or for fibre lined kilns. The results of element conditioning can be quite dramatic. It may not have much affect for normal, low temperature firings, but can be significant for harsh operating conditions."

Welcome to the forum.

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Thank you Min! I didnt know of Glazy so there's an awesome resource for me. I also had not heard about conditioning the elements so i will look into that more. I will read the whole manual and everything when the kiln arrives and I'm assuming all this stuff will be covered in there...

And wow amazing the difference in element life span 100 degrees makes! 

I'd love to hear from anyone who actually fires to cone 10 in an electric kiln!

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Make sure you get the upgraded hi temp elements -call them if you have have not already thought about this. Also a 3 zone is best and type S thermocouples will work best at cone 10. Upgrade that also if you are palnning a cone 10 firing range. I have. afriend with atht upgraded skut who fired to cone 9-10

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The first kiln I ever knew was fired to a 9 on household wiring with standard elements for close to 20 years with no issues.

We upgraded to a digitally controlled kiln and continued firing to a warm 8 or cool 9 for another 20 years with few issues.

The elements lasted about 30 firings and we had some trouble with thermocouples one year. I can't remember exactly but it was some manufactures defect that affected more than just out little cottage kiln.

I enjoyed helping dig up local sources of whiting and feldsar. We also had access to very nice secondary clays and other minerals for all sorts of testing.

During a time when ^11-12, heavy reduction was the common practice we were happily producing greens and reds and even a nice yellow along with a chun-like opalescent white and very promising oil-spot series I never found the time to work out. Of course there were was a finicky tenmoku and a floating blue which I thought was a wonder glaze until I found out everyone already knew all about it. The internet didn't exist for us yet.

I still sort of miss my work in oxidation. I left many unfinished and promising tiles.

I can post the recipes if you want to try them. It would be fun to see if they like you as well as they did us.

cheers

Edited by C.Banks

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There is almost nothing you can do at cone 10 oxidation that you can't do at cone 6 oxidation. The big difference between most cone 10 and cone 6 work is that most people who fire cone 10 do so in a reduction atmosphere. In oxidation there's no need to go that hot.

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On 10/2/2019 at 9:05 AM, neilestrick said:

There is almost nothing you can do at cone 10 oxidation that you can't do at cone 6 oxidation. The big difference between most cone 10 and cone 6 work is that most people who fire cone 10 do so in a reduction atmosphere. In oxidation there's no need to go that hot.

As I grew up I realised more how unique our situation was. We had to move around for a few years so a brick kiln was not an option and the stoneware temperatures made working with found material a bunch easier.

We did eventually find the bricks to put a nice kiln together but it took a while.

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Thank you everyone!! I really appreciate your feedback! I think I'm going to change to a cone 6 situation to keep my elements happy longer, but I need to do at least one or two cone 10 firings first as all the work I have drying is cone 10 clay... but seems like it won't be too much of a problem.  

On 10/1/2019 at 6:09 AM, C.Banks said:

The first kiln I ever knew was fired to a 9 on household wiring with standard elements for close to 20 years with no issues.

We upgraded to a digitally controlled kiln and continued firing to a warm 8 or cool 9 for another 20 years with few issues.

The elements lasted about 30 firings and we had some trouble with thermocouples one year. I can't remember exactly but it was some manufactures defect that affected more than just out little cottage kiln.

I enjoyed helping dig up local sources of whiting and feldsar. We also had access to very nice secondary clays and other minerals for all sorts of testing.

During a time when ^11-12, heavy reduction was the common practice we were happily producing greens and reds and even a nice yellow along with a chun-like opalescent white and very promising oil-spot series I never found the time to work out. Of course there were was a finicky tenmoku and a floating blue which I thought was a wonder glaze until I found out everyone already knew all about it. The internet didn't exist for us yet.

I still sort of miss my work in oxidation. I left many unfinished and promising tiles.

I can post the recipes if you want to try them. It would be fun to see if they like you as well as they did us.

cheers

C. Banks, the thought of digging up your own clay sounds amazing! What an awesome experience... would love to be able to do that one day! 

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On 10/15/2019 at 12:12 PM, nic moore said:

Thank you everyone!! I really appreciate your feedback! I think I'm going to change to a cone 6 situation to keep my elements happy longer, but I need to do at least one or two cone 10 firings first as all the work I have drying is cone 10 clay... but seems like it won't be too much of a problem.  

C. Banks, the thought of digging up your own clay sounds amazing! What an awesome experience... would love to be able to do that one day! 

The local clay was more a silt and good as a substitute for Barnard or Albany slip. We were never fortunate enough to find a throwing body other than a fun, earthenware experiment.

Shale is another source for clay.

It was more work but the road trips were fun and the work, for us, was worth the results.

Edited by C.Banks

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