Well, I unloaded the firing at zero-dark-thirty this morning! Just when you think you know what you're doing, the kiln will surprise you - or at least, me.
I knew this firing was different than the most recent firings before it. The back-pressure flame was very transparent, even once the sun had set, which usually makes the flame more visible. Even if I pushed the damper all the way in, the flame didn't get any longer, although I did get back pressure out the burner ports, which would indicate a very heavy reduction. So, weird mixed signals all around. The kiln also stalled for nearly two hours with ^11 bending on top & ^10 just barely tipping on bottom. Nothing I did would move those cones! Eventually I had to turn the kiln off, mostly out of concern that a long hold at 10/11 would cause warping.
Small blessing: that didn't happen. In fact I had only one second in the entire kiln, and that a very minor flaw: one mug got a piece of wadding stuck inside, but it was a very small piece and I can make the resulting flaw almost invisible with my trusty Dremel tool.
But the pots are very pale, obviously oxidized. I am always hoping for that golden tan that is a common soda-fired surface on b-mix, and which I got quite successfully in the last two firings. I'm not too disappointed - they aren't what I hoped for, but they have a delicate prettiness of their own - but I am a bit worried because I don't know why this firing was different. It may be that in my efforts to tip those cones during the stall I inadvertently slipped the fire into an oxidizing state? I feel like I would have noticed that! But I don't have a better explanation.
Anyway, that's clay life for ya! I've never been one to hide my errors or pretend to perfection. I think it's important for students & early-career potters to know, they aren't screw-ups! Clay is just like that; there are so many variables that we all get unexpected results sometimes.
If you want to see the pieces in real life, many will be at the Portland Pottery Holiday Show, December 13th - 24th, from 9 am - 7 pm. Also, you are my invited guests to the opening night party, Thursday December 12th from 5 - 9 pm. I'll be tending bar in my festive finery!