Tuesday, September 4, 2012

Seventh Firing of the Train - The Wreck Continues

I'm trying to catch with my blogs - just too much to do in the summer!
The early July firing was my last chance to fire things before the Salt, Soda and Wood show that I am taking part in from mid July to end of August. In the front section top and bottom it was a repeat of the last train disaster - the 6th firing at the beginning of June. So it was not the hard bricks and under firing, it was not the fault of letting the pots with MD shino sit around in the damp and fog - it was something that was happening in the first part of the flame path where there is the most ash, flame and unburnt gases.

Also none of the blistered pots didn't remelt when I had put them into the gas kiln for another cone 10 firing. Even if reglazed with another glaze the bubbles and blisters stayed - so obviously the MD shino had the flux -  probably the soda - vaporize and so the bubbles could not smooth out.
So not sure what is making all the soda vaporize. Again this wood was mostly soft wood - white and red pine that has a lot of resin and probably somewhat damp for some pieces. Also all had bark on it.
Another possibility  - perhaps reduction cooling? Would the gases cause bubbles? In both firings I did not let the embers burn down that much before clamming up as in previous firings - both times due to just being too tired.

Still in the previous 5 firings any shinos in this front section were fantastic - in fact my favorite place for shinos. So I am pretty leery of doing another firing - will have to get other glazes for the front section.
It was a good thing that I had saved pots from last year for the show otherwise I would not have had many pots to put in.

The middle section was not bad, the white salt was pretty good. The tail end - still had some unmelted ash on the pots which when put in the gas kiln did smoothed out.

1 comment:

  1. Do you have more detail on the specifics of your kiln? I am I correct in thinking that this is the kiln used for your current work. I live in Gore Quebec with great interest in wood kilns. There is a beautiful wood kiln located in BC that Jinny Whitehead and 3 wonderful potters fire together and a great Vimeo video of them working together.