What tool scores a cut line into glass for stained-glass making?

A glass cutter scores a cut line into glass for stained-glass making.

The tool uses a small hardened wheel, traditionally made of steel and often made of tungsten carbide in modern versions. The wheel does not usually saw through the sheet. Instead, it makes a controlled score that weakens the glass along a chosen line, allowing the maker to separate it with pressure or specialized breaking tools.

After scoring, a craftsperson may use grozing pliers to nibble away small irregularities and refine the shape. The finished pieces are then fitted into the design and joined, traditionally with lead came or by copper-foil construction.

A glass cutter is different from a lead knife, which trims the lead channels, and from a soldering iron, which joins metal seams. Confusing these tools can make the stages of stained-glass construction difficult to follow.