Hi everyone, I'm kind of new to enameling and have been given the opportunity to explore for the store that I work at.  I've had a couple successful pieces, but recently I'm having issues with the enamel cracking, and, in some cases, coming off completely, while I'm trying to clean off the oxidation and polish the metal.  I'm using 20ga 18KY, but the enamel is going into recessed areas. I'm guessing the metal is flexing too much, but I could really use some advice.  Thank you!