first firing of 2013

I glazed the pots and packed the kiln one sunny day in the snow, sieving the ice out of the glaze bins and finding it quite pleasant working outside, but the next day the forecast was for an east wind, which blows out the burners on my kiln, as the duct that acts as a chimney opens in the middle of the gable end, which faces east. in fact there was very little wind, but I judged it safer not to try. this situation went on for seven days until the wind finally turned.

anyway, it was an interesting firing; I lit it a little late, at seven thirty in the morning, and turned it off earlier than the last firing which I lit at six thirty, but I ran it at a higher pressure than before, with quite a lot of reduction, soaked it for an hour at 1008C, and turned the pressure down a bit when cone nine had gone, to give it less reduction – only half an hour after that cone ten had gone over and eleven was just bending slightly – as you can see below. so a speedier, more reduced firing, and it gave me everything I wanted. good ruddy oranges on the copper dolomite glaze, no pink on the magnesium cone nine glaze on the bottom halves of the chalk beach pots, just the right temperature for that glaze in fact.

and you can see the three frozen snow bottles tucked underneath the shelf – this is a horrible spot for most of my glazes, but fine for that combination.

there was a lot of green flame, the copper burning off these saltmarsh pots which were all near the burners.

a 100% successful firing.

I put two of the new porcelain pod pieces in, and they fired beautifully. the cracks which were present at drying got no worse.

I had to dump several pieces which split and then opened up like this. it’s probably partly that I need to make the inside of the shape the side which was last uppermost during rolling out. I tend not to because the porcelain takes up an imprint from the plywood boards, but I found that in fact I can scrape this off with a metal kidney.

this is the black glazed one

above is the other porcelain piece finished and below after drying. I glazed it with the same combination as the stoneware pod shape below. the magnesium glaze has reacted quite violently with the barium, and made this curling off crawl, which I like. luckily no pink staining from the copper glazes.

I made a lot of this shape in the various clays I have around. this is the grogged white stoneware from earthstone, with the sand from my finca added, mostly this gives the little nodules of feldspar you can see, plus various crusty little lumps. I have glazed it, and several of the other pots with first a dunk into the barium carbonate dry glaze, then the other end and an overlap in the old magnesium crawling glaze. this is cone nine and likes heavy reduction, but on the bottom half it is fine in my cone ten firing as the kiln is a lot cooler at the bottom.

on this very cracked bottle I tried pouring the glaze. I must do this more often, it has worked well.

this big bottle in the pizza clay has been languishing in the workshop for about eighteen months because the first one I made looked awful, really anaemic after firing with my shino glaze. basically there’s not enough iron in the body to get a good result with the shino. but with heavy reduction this barium and magnesium overlapping combination has worked very well.

I like the way the magnesium glaze has crawled and gone very grey.

there are lots more “pod” forms in my workshop waiting to be fired, especially in porcelain, and several “flagons” as I have found the fat bottles with the little handle/flange should be called. you can see the rest of this firing here