Pattern shears for copper foil work
Pattern Shears For Copper Foil
Pattern shears are special scissors which, when cutting out your templates for copper foiled stained glass making, removes a thin strip of paper, equal to the amount of gap needed to allow for the two strips of foil where your pieces of glass meet.
To use, simply draw out your cartoon, cut along the lines with the pattern shears, which remove the gap required, and use the cut templates to start cutting your glass. This works with lead work as well.