Grid Lines

Grid lines are collections of horizontal (and/or vertical) lines that divide a chart into a grid, making it easier to read values of the chart. To enable or disable grid lines for either the x or y-axis you just need to set ChartAxisX.PlotStripWidth or ChartAxisY.PlotStripWidth:

<shield:ShieldChart runat="server" ID="ShieldChart1">
        <shield:ChartAxisX PlotStripWidth="1" TicksWidth="1px" MinorTicksWidth="1px" DrawColor="Red" 
            CategoricalValues="Jan, Feb, Mar, Apr, May, Jun">