[nancylee]

Hi,
I think I am confused. I was watching some Robin Hopper videos and I could swear he said that he only fires once - he doesn't bisque, then glaze, then fire hotter. Is this true, or did I mess up in my understanding of what he meant??? As an impatient person, I would love to be able to glaze greenware and then fire once!! Thanks for any help,
Nancy

[Mark C.]

I do not have current RH info but do own several bisque and glazed fired cone 10 pieces he gave me a long time back. At that time he was bisqueing-but really its about what you want to do-not him. Single fire you can do if you want-its way slower on the glazing so an impatient maybe for twice firing?
Mark

[Lucille Oka]

Ditto what Mark C has said.

Why not make a test and see if 'once fire' works for you? Make a test piece and glaze it and fire it. Just so you know at the outset greenware is 'chancy' dipping into glaze; if held in glaze too long it may get too soft and fall apart in the glaze vat. So brushing on glaze maybe best for your first try.

Remember to load the 'once fire' ware into the kiln like a glaze firing, fire slow like a bisque fire, and fire to the maturation temperature of the glaze.

Robin Hopper is a Master Potter and you don't get that way without testing. I am sure he has tried it all and has failed and succeeded over and over. The key is to test a technique and see if it works for you.

[nancylee]

Thank you!! Yes, I will test before I ruin a piece I like!
Nancy

[bciskepottery]

John Britt has a chapter on single-firing in his book, The Complete Guide to High Fire Glazes. Although written to ^10 firings, the principles apply to all temperatures. You may need to adapt your glaze recipes -- and how you adapt may depend on whether you apply the glaze at the leather-hard or bone-dry stage. Glazes formulated to go on bisque ware already take into account an initial firing where the wares shrink; some may work without any problems, others may need adjustments. And you'll need to fire slowly -- your single firing will have to accomplish all the chemical changes -- removal of water, burning out of organics, etc. -- while also dealing with a glaze on top. Steven Hill single fires -- both his older ^10 and his newer ^6 -- work; he uses a sprayer to apply glazes.

[clayshapes]

bciskepottery, on 10 June 2012 - 09:39 AM, said:

John Britt has a chapter on single-firing in his book, The Complete Guide to High Fire Glazes. Although written to ^10 firings, the principles apply to all temperatures. You may need to adapt your glaze recipes -- and how you adapt may depend on whether you apply the glaze at the leather-hard or bone-dry stage. Glazes formulated to go on bisque ware already take into account an initial firing where the wares shrink; some may work without any problems, others may need adjustments. And you'll need to fire slowly -- your single firing will have to accomplish all the chemical changes -- removal of water, burning out of organics, etc. -- while also dealing with a glaze on top. Steven Hill single fires -- both his older ^10 and his newer ^6 -- work; he uses a sprayer to apply glazes.

[clayshapes]

Hi there is another thread on this topic in this section somewhere -- I started a few weeks ago and got some really good advice about single firing. Just search single firing and you will find it. Lots of detail and links to follow in that thread.
Good luck!

[SShirley]

Steven Hill fires once to cone 6.

[perkolator]

in our studio we do 95% once-fired work. students are on a 10wk quarter system and really only have 8wks to work since the 2nd to last week is firing and last week is critique and cleanup. if we bisque fired everything there is no way we'd get anything done on time.

most of the work produced is sculpture, mostly large-scale, and some functional work. most of the time we are firing at ^04 oxidation, but also work at midrange ^5-6 ox/red and seldom at stoneware (for sculptures). 90% of the time, with our clay body, our glazes come out just fine - but there are some combos that don't quite work and result in less-desirable surfaces (or maybe not for personal aesthetic) which is why you should ALWAYS TEST. obviously, some things just won't work - like dipping a thin-walled pot in glaze; but you adapt and learn how to overcome.

single-firing is(was) a very common practice for ceramics and pottery for thousands of years. Also, just think of how much more fuel and time you're consuming if you have to fire the same object twice for the same result. But single and bisk/glaze firing both have their places, you just have to figure out which works in your situation and weigh the pros/cons of each. Whenever I test a glaze I always do one on bisque clay and one on greenware just so I know how each reacts.