I am having problems with some of my work.
After I have done some coldwork, either with my grinder or saw, and then firing the piece, i get a dull edge on the piece which is clearly the area where i have done the cold work!!
I have tried heating it up slower.. a longer hold time (worried about devitrification) at the top. Changing the top temperature from 790 up to 820 degrees C. I have followed the advice to keep the piece wet after cold work, and then cleainng it with nail brush.. But the results stay the same. You can see the edge of the cold work.
Can anybody please advice me on how to solve this issue?