【ステンドグラス教室第18回】マルトリンハンマー使い方。stained glass how to

[@CP-fe6jr]

this technique is new to me, I much prefer the Morton safety break for simple cuts like shown here. But if I do want to tap it why not turn the glass over and tap what then becomes the top?

[@stainedglasschannel1102]

It is important to crack both ends of the glass.