Plugin to create perfect curves for CNC / Laser cutting

[GavinG]

I have been using Sketchup for ages, however the only challenge I have with the program is the inability to create a perfect curve for CNC routing or Laser cutting. Is there a plugin / solution available that will allow a sketchup model to be sent as a 2D dxf / dwg so as to eliminate the facets that make up a curve to a smooth line? I use the program to design custom lighting products.