I do a lot of black and white line drawings that I would like to vectorize for use with my CNC machine. I normally scan the drawings in at 600 DPI, then clean up the bitmap a little bit. My end goal is to have a nice vectorized drawing similar to what the centerline bitmap trace puts out. The centerline trace does a terrible, unusable job. It generates thousands of points, which is very difficult to clean up and doesn't trace accurately at all. All of the outline trace options give me great looking vector drawings, except that for every line in my drawing there is a curve drawn on each side of every line. That doesn't work very well with my CNC software.
I have mostly just switched to tracing the image by hand using beziers. This works, but seems slow. It really seems like there should be an automated way to do this. Does anyone have any suggestions? Is there something I should be doing with my input files? Is there a technique I could use to make this easier?