Cone 6 firing schedule for SCM etc glazes

[June Perry]

I spent the past few days throwing a large amount of test tiles using 3 different cone 6 bodies to test both in cone 6 oxidation and soda. Can someone please share their cone 6 oxidation schedule for me to test both the SH glazes and my own cone 6 calcium matts and other glazes.

Stevens higher cone firing schedule is on his page, but not the cone 6. From what I have garnered reading some messages on the group, the schedule is  6 to cone 6 1/2, hold 1 hr, fast drop to 1600. Is there a hold at 1600? Also, is this the correct schedule? My tiny test kilns are manual and my bisque electric kiln is pretty big, so I don't want to waste all the work throwing, trimming and glazing around 100 tiles for the C6 ox firing, by not using the right firing schedule.

 

Thanks for any help!

June

http://www.shambhalapottery.com

http://www.shambhalapottery.blogspot.com

 

[Jan Wallace]

Hi June. Thanks for asking this question. It is good timing as I am about to test various cone 6 glazes (mostly found on this site) and am a little hesitant to start before I am sure what I am doing with respect to 'firing schedules' and 'glaze application and combinations' . I have also been reading through the various comments posted by members which differ a little in relation to firing schedules. I am interested in using the C Harris Tenmoku, Nutmeg, Licorice, Jen's Juicy Fruit, Water Blue & Green, Variegated Slate Blue, Zinc Semi Matt Blue, Chrome Tin Red, Waxy White, Val Cushing's Green Ash, Hanna's Fake Ash to name a few. As I have iron glazes, which i will prob use as bases then use others over ??, I am wondering about the soak period/schedule. I also have hundreds of test tiles ready to go on my bench but have these questions as I have a small manual kiln. Thanks in advance to anyone with any input.

[June Perry]

You have a couple of glazes not on my "to test" list. Are all yours glazes Steven Hill is using?

I have most on your list, but also have Pier black, Oribe, Cornell Iron Saturate, Spotted Black, and probably a clear which Steven mentioned as using over some other glazes.

 

After reading all the posts here, I compiled some of the info, but I don't know if this is the one Steven uses for these glazes:

 Slow fire to cone 5 temperature, plus an additional 20 degrees F. Hold 1 hour then fast cool to 1700F. Soak at 1700 for 1 hours. Then fire down 50 degrees per hors to 1600. Then shut down.

(George Lewter recently posted that Steven is now doing an uncontrolled drop after the top temperature soak); but that may affect good developement of red if one is using saturated red glazes in the firing. Also, I don't know what Steven's current schedule is. He may be firing very slowly at the point the glazes are softening which may assist in crystal development on the way up as well as during the one hour hold.

[Jan Wallace]

Thanks June. Firstly, i want to say that i really enjoyed reading your blog and website. It is my goal in the next 12months to pull down a wood kiln I built some years ago and build myself a soda kiln, so I was thrilled to see your work and hear about what you do. What a wonderful studio you have and a beautiful setting. Thank you also for sharing your wealth of information on your website.

I have only a few of SH glazes (found on Lakeside Pottery website) and others that I found on this site by browsing for hours. I have others too that I have come across here and there and written in my recipe book that I have had for years. 

What you have said makes sense. I do have a few of the iron glazes and as I understand it, they are more sensitive to the cooling / soaking cycle. I have been writing down a few things I have read on this site too, and one suggested schedule that came up a couple of times was - Fire to Cone 6, a hold for 25 min, 500 deg drop to 1900, a 30 min hold there, then 125 deg down to 1700, then off. Which i think i read somewhere is the firing schedule from Mastering Cone 6 Glazes (i do not have the book). Any schedule will be a little touch and go for me with a manual kiln i think, not the control of a computer controlled kiln, but at least its something to go on. Thanks again.

[June Perry]

The MC6 glaze firing schedule works very well for their glazes; but from what I gather from reading posts here, it will create very sharp crystals on the surface of some of the Steven Hill glazes which will require a lot of sanding with silicon carbide paper. The SCM which is the basic base glaze that Steven uses, has a lot of crystal forming materials in it, i.e whiting, titanium and lithium.

 

All my tiles are done and drying, so after I trim a few bowls today, I'll start batching those C6 glaze tests; and if I don't hear back from anyone who knows Stevens' current firing schedule by the time I'm ready to fire , I'll just use the one I posted above. I've already tested some cone 6 glazes in a straight, no firing down schedule (all those on my web page), so I'm going to redo some of those on new clay bodies with the Steven Hill firing schedule that I could figure out from the posts in the group, and see if one schedule will work for all of them.

 

[Jan Wallace]

Yes, I read that too with the SCM. I dipped at least 150 test rings today and i will leave them to dry until I get time over the weekend to fire them. I will probably try the Mastering Cone 6 schedule, or at least a slow cool from Cone 6 as i have a few iron bases I want to get right. I am not using the SCM at all so perhaps not as vital for me to follow the Steven Hill schedule i guess, even though i am using a few of his other glazes. Will be interesting to see the results. My first time at real glaze testing, so a little apprehensive and excited. I have made some of my own glazes in the past but not to this extent, but was also at college so used their foolproof glazes and firing service, so did not really learn a great deal that way. Looking forward to seeing both our results. I am going to document my firing to try to replicate if i am happy with what i get. Happy firing. :)

[Joe Shaw]

the Oregon Potter's Guild newsletter dated February-March 2011 has Steven Hill's firing schedule.

http://www.oregonpotters.org/documents/newsletter/2011/feb_2011_mem...

There is a hold of 3-0-60 minutes at 1600. He fires to cone 5 and lets soak until cone 6 drops (about an hour). Download the newsletter, it has the single fire schedule and the schedule for bisque-fired pieces.

[Jan Wallace]

Thanks alot Robert, that is very helpful. I will have a look at that now. :)

[June Perry]

Thanks so much Robert! This was a big help!I've made a note of both schedules since I do bisque.

 

June

http://www.shambhalapottery.com

http://www.shambhalapottery.blogspot.com

[June Perry]

Good luck with the firing. Mine is about two weeks off. I have a lot of glazes to batch, mix, sieve and get on tiles and still have other pots to trim, decorate and bisque for my soda kiln as well.

Can't wait to hear how your firing goes! Did you see the post that Robert Shaw posted with the link to the Oregon Potters February 2011 newsletter that has Stevens glaze firing schedule for both raw and bisqued ware?

 

June

http://www.shambhalapottery.com

http://www.shambhalapottery.blogspotcom

[Jan Wallace]

Thanks June, yes, i printed out the page with the schedules. Very helpful. I am going to do a firing tomorrow, so i will let you know how it goes asap. All the best with yours.

[Belinda Willis]

I have Steven's firing schedule as of the summer 2011. He fires to 2170 with a one hour hold. That temp is a ^5 temp but with the long hold, ^ 6 goes down in his kiln. He does a natural cool to 1700 degrees then a controlled cool of 50 degrees an hour down to 1600, hold for one hour, continue controlled cool of 50 degrees an hour down to 1500 then he turns off the kiln.

He says this schedule will probably change as he tweeks the cooling ramp over time.

[June Perry]

Thanks Belinda. I 'll have to try that one.