Wednesday, September 21, 2005

Cone bending

1240 degrees on the pyrometer,cone 7 half over at the top spyhole,a touch cooler on the bottom [about 1/4 cone,maybe 6-7 degrees]-more or less the way I [and the pots] like it.The previous kiln-fired Monday-came out well,despite a slightly less even firing:I think I have just learnt not to crash-cool the kiln,which I had been doing recently-and losing some reds as a result [I think] through reoxidation.It's very difficult to know exactly how the causal links flow in a firing,partly because one is understandably unwilling to take too many risks with a couple of weeks' worth of work to try to disentangle the parameters.Hearteningly,no-one else seems to know much more-a recent discussion in Ceramic Review [#215]on how to fire in reduction offers almost all possible alternatives-reducing only 'til 1150,oxidising at the end of the firing,or not.Take your pick.I have always reduced fairly strongly from a nominal 920 degrees until shutdown,and will henceforth and thereafter close the flues off sharpish,believing that this will promote reds until someone convinces me otherwise.
Looking around the studio,I see that I have another kiln's worth of pots to fire,but nothing to put at the bottom of the kiln,which tends to like only the clear glaze-usually over slipped stoneware.Some stoneware bowls I made for this very purpose got left out of the last bisc,and the only other bowls are porcelain.Maybe I could glaze the porcelain bowls in the clear glaze and lustre them for the next lustre kiln...or raw-glaze the stoneware...either way,I think that kiln #3 is going to happen sooner rather than later.
We're at 1251 now-both cone 8's down,cones 9 neck and neck leaning at 2 o'clock.It's half-past ten,so I should get to bed at some reasonable hour.Will try to post pictures tomorrow...


Post a Comment

Subscribe to Post Comments [Atom]

<< Home