Weight (in points) of:

• grid border
• vertical lines (may be a vector)
• horizontal separators (may be a vector)

The default is 1 0.8 0.01.

To frame the entire table, with no other gridlines:

leaf.table.Gridlines 1 0 0

To rule vertically after alternate columns with hairline separators between cells (use 0.001 to ensure you get the thinnest line your printer can draw):

leaf.table.Gridlines 1 (0 0.5) .001

To rule horizontally after every 5 rows of data:

leaf.table.Gridlines 1 .5 (0 0 0 0 1)

See also ...
leaf.table.Rounding