How do I clean the backs of my copper blanks after firing to remove scale? I’m getting flaky surfaces as shown in the image below.
We stock a product called Antiscale which should reduce the backs of the blanks scaling.
If you haven’t used antiscale and want to remove the scale then try mixing a tablespoon of vinegar with approximately half a cup of water and soak the blanks for a couple of hours. This should remove the heavy scale. (scale is always heavier when torch firing.) You could try wire wool but be very careful not to bend the blank so it doesn’t crack.