NcPlot converts in the order the geometry is created in. If you create the lead-in arc on the first layer
followed by the 3 inch dia.circle on the second layer then the lead-out arc on the third then export, you
should get what you want. To verify this, type in the following in NcPlot:
G0X1.4Y-.1Z0
G3X1.5Y0J.1
I-1.5
X1.4Y.1I-.1
Then export DXF and import DXF back in, you'll notice the geometry will be in the same order as coded
hope that helps