Just had my first run at pit firing, which was a huge success. By that, I mean that I went in to this expecting everything to break, and only half of them did. And the ones that did break are still largely usable. They just look like they went through a minor battle.
I’ll gather up the photos and notes below and use this as a space to figure out my timing. The broadest lessons learned so far are:
- Start slower
- Finish way slower
- Pile on more wood and get it hotter
Fire got started a bit after 2pm. Mix of wood, charcoal, and lighter fluid. Fire stayed relatively small – in retrospect, I should have built it up hotter from the start. I’ll get to that in a bit.
2:25pm – The pieces have all been added to the fire pit. They’re starting to warm up. They’re staggered a bit, but packed in quite well. On average, I think they were roughly equal distance from the heart of the flame.
2:52pm – Moved the pieces all closer to the fire by a few inches. The actual burning portion was rather small, and it didn’t seem to be putting out much heat. This is probably good for slowly warming the pieces, but it seemed remarkably slow to change anything. There wasn’t any color shift, and the damp pieces weren’t drying out in any way.
3:06pm – Moved everything a little closer to the fire again. Now only inches away at the closest pieces. The damp pieces on the wings still aren’t showing any change, but the closest pieces are turning a darker sort of grey. Though I didn’t know it at the time, the ashen ground underneath the pottery was heating up to quite a degree. This, as much as anything, was warming them up.
3:24pm – The closest pieces and a few inches back are definitely showing some color change. The very closest pieces are touching the fire and turning black. Some are resting on colas, some on wood. This is likely where I should have gone more slowly, rather than at the earliest movements (or both, now that I think about it). I heard some popping and cracking here, but it seemed to be coming from the wood more than anything.
3:35pm – I’ve started covering some of the closest pieces with charcoal and chunks of wood. They seem to be able to take the weight without issue, but some of the pieces are starting to break apart. They don’t do damage to nearby pieces, but some of the chunks can fly a few inches. The damp little scoop shape with thick walls was one of the first to break. It was still relatively damp when it was getting near the wood – I’m not sure why it was so stubborn about drying out. I’ll make sure to air dry more thoroughly in the future.
4:00pm – Starting to really cover the pieces up. It seems like the breaks are happening in thicker pieces, areas where joined by slip. or in pieces that started the process while still damp. I’m definitely rushing this portion of things, especially with the fire so weak. It doesn’t project much heat, so the transition to direct contact with charcoal must be very intense. I should have had a much larger fire, and moved to rotate and cover the pieces more slowly. I was pushing everything with a stick, so I didn’t have a solid means of actually turning them around.
4:21pm – The pieces are all touching charcoal or wood right now. By no means can I say they’re all completely covered – there’s plenty of gaps up to open air. I really should have brought more fuel, but I didn’t quite anticipate the room I’d need to cover. I also didn’t expect having so much room to work with. I’ll be sure to plan out the preheating portion, maybe form the wood into a crescent to heat around a pile of ceramics. Use some tongs to rotate them.
4:46pm – The fire is definitely dying down, and all the charcoal is pumping out heat from under ashen exteriors. Many corners are starting to come up in open air. This was likely not enough time for everything to properly cure (sinter, I guess?). The colors are tending towards white, though I later found out this was simply due to the ash. Underneath, they were turning red and black and grey.
5:22pm – the pieces are still mostly covered with charcoal. For the most parts, cracks seem to have stopped forming. If it was going to break, it would have done so by now. There’s still a pretty good amount of heat coming from the pile, but even from 3 feet away it is nearly imperceptible. There’s just too little burning stuff to fully cover the pile. Lesson learned!
5:23pm – The pieces are starting to be revealed. This is mostly my fault, as I’m poking things to uncover them more quickly. I figure there’s not enough heat present here to be worthwhile, so it’s best to just let things cool off. I don’t want to be here all night!
6:31pm – I’m pulling pieces from the fire as they become cool enough to hold. I’m being pretty cautious about holding my hand over the pieces and tapping them gently. The ground is holding a ferocious amount of heat, and the pieces need to be pushed to the sides bit by bit. They seem to be cooked well enough, and they’ve hardened well. I’ll test them later by soaking them in water.