Always lead to the cartoon line, not the glass. This ensures accurate completion of the panel. If the glass is slightly too small, the cement will take up the gap (assuming the flange of the came covers the glass – if not, you need to cut another piece of glass that fits). If the glass overlaps the cut line, it needs to be reduced. A description of the process is given here.
|This shows the use of a guage to determine where to cut the horizontal lead came.|