Hi Karl,
By default the in fit bounds mode the chart will always try to fill as much as possible from the chart panel content bounds, without breaking outside. If you want to disable this feature simply set the bounds mode to none:
nChartControl1.Charts[0].BoundsMode = Nevron.GraphicsCore.BoundsMode.Node;
Hope this helps - let us know if you have any questions.
Best Regards,
Nevron Support Team