Question: To make a detailed engraving on glass,
Option 0: apply masking tape to the entire project, unless you are expert at using an engraver.  By masking off you not only add protection to the glass, but also make it easier to follow a towel.
Option 1: apply masking tape to the entire project, unless you are expert at using an engraver.  By masking off you not only add protection to the glass, but also make it easier to follow a template.
Answer: 1