Glass cutter
From Wikipedia, the free encyclopedia
A glass cutter is a hand tool which aids in the cutting (strictly, the controlled breaking) of flat or pane glass.
[edit] Construction and Use
The working end of the tool consists of a small hardened-steel, carbide, or diamond wheel. This wheel is rolled across the glass, along the line to be cut, while applying considerable pressure. The pressure applied by the wheel does not cut the glass, but rather causes a small, localized, linear failure at the surface of the glass, resulting in a score line (essentially, a deep scratch). Next, the glass is flexed across this score line, often while pressing the back side of the glass against a straight rod or table edge aligned with the score. The result of this action is that the glass breaks — but if the scoring and flexing maneuvers have been correctly performed, the glass breaks with a single, clean fracture exactly along the desired line.
To ensure that the cutting wheel rolls freely on its axle in spite of the pressure on it, the head of the cutter is dipped in a lightweight lubricant before use, often kerosene.
The glass cutter also has some notches which can be used to grip the edges of small pieces of glass as they are being snapped, and a ball (in effect a miniature hammer) which can be used to tap on irregular pieces to induce them to fracture.
