Sunday, October 11, 2009

New Pots From Old

I dislike wasting things, but inevitably a firing will produce some failures- a glaze that went wrong, firing cracks or pieces that looked OK at the time but didn’t cut the grade when finished. I don’t want to sell seconds. I have seen failed pieces by good potters emerge in Op Shops, and I really don’t want my mistakes to come back to haunt me. I keep some of the “better” failures to use ourselves, but with the remainder, I’m trialling crushing the fired glazed ceramic to a coarse powder and mixing it into fresh clay as “grog”. (Grog = gritty material added to a clay body for texture, to reduce firing shrinkage or to improve resistance to thermal shock from sudden temperature changes.) My first trials have been promising. If results continue to be good I might want to acquire some kind of small hammermill. For my current small quantities I’m using a mortar and pestle (and a good dust mask- I don’t want to develop silicosis).
The clay pictured contains crushed ceramic that I had coloured with a blue pigment. When glaze fired the glaze on the grog melts into small droplets that speckle any glaze applied over it.


  1. What's a hammermill?

  2. A hammermill is a device with a series of "hammers" set on a rotating shaft, used to pound up rock or similar materials. Sovereign Hill has some very large scale steam driven versions for pounding up gold bearing ores. Very noisy in a fascinating way.

  3. Hmmnn, thanks some food for thought there. I don't have a hammermill either but I make small pieces so I'll give it some more consideration.