The grooves on a glass cutter, typically near the cutting wheel, are used for controlled breaking of the scored glass, especially for smaller pieces or tight curves.
These grooves help to initiate and guide the break along the score line. Some grooves are designed for specific glass thicknesses.
grooving
What are the grooves on a glass cutter, typically near the cutting wheel, used for?
https://youtu.be/fO-7SFmWbK8?si=t1Uf9A9R3-5R_OXD
https://youtu.be/RHbyVeGScnE?si=DwtfZSSZqPGkJ-Id
https://youtu.be/rffoPrBdWd4?si=CUXwXShzEEquXI1k
https://youtube.com/shorts/Qfsqy6L_BgE?si=x2nmlm-NL9XNMmdv
https://youtube.com/shorts/tAIQjrV1M8I?si=40Kh1T3D9gkiBhkx