I have been having adventures with plates. As the title hints, and the picture above shows, they have been warping during the glaze firing.
Not satisfactory, and cue for some more in-studio and on-line detective work.
It seems this is a common problem – and that every potter has different tips on how to stop this happening. These included
- not firing them on props, but on a flat base
- not bending them whilst moving from the batt to the drying board
- using waterproof batts that they can dry to leather on
- supporting the turned section of the base with a special alumina & clay mix
I re-fired the wiggly ones above without props and that reduced the wiggles – in fact the picture is post re-firing so you’ll have to imagine how undulating they were before.
The deduction was that the remaining wiggles were caused by clay memory retaining bends caused by moving the damp plates. I have changed the way I move them, now sliding them vertically off the old batt onto my outspread hand and then horizontally onto the drying board. As you can see from the pic below this has helped considerably!
I needed some more batts anyway so have ordered some marine ply ones. Apparently they will ‘pop off’ when leather hard and ready for turning – thus reducing the need for handling and moving whilst damp. The first batch were thrown today… watch this space!