I have a brew kettle which has stick on volume markings that are falling off. I read about using a 9 volt battery to etch volume marking into the side of the kettle. I want some sort of stencil to use to form the markings. I went to Joann's today but they didn't have anything. I tried Amazon but didn't find anything either. Does anybody have any suggestions as to where I could buy volume marking appropriate for a brew kettle? Thanks.