I'm having a similar problem with using multiple axes. When all the series are removed from an axis, the axis becomes unusable for adding more series. To get around this problem, I would make a new axis whenever all the items were removed from the old one.
Now, we want to have strip lines from the ChartGrid show up. With the above solution, I was not adding the axes to the chart, so the ChartGrid was not showing the strip lines.
To associate the axis with the chart, I added this line to set the chart's vertical axis to the newly created axis. This works until all the series have been removed from that axis and a new LinearAxis is created the 2nd time through.
Am I doing anything wrong with this, or is does reassigning a chart's vertical axis cause a null reference exception?
Is there something other than making a new axis that will get the old one to continue working?
Thanks