I am new here . Help. I have pasted a model airplane part and saved it . There are lines indicating balsa wood which i want to remove . When i out line in red using the eraser tool and release the left button of the mouse the drawing disapeers how should i go about this as i am lost. I know for user's experienced its a dumb ? Can some one direct me step by step ? The ultimate goal is to send the image to a tool path and g code software program for cnc cutting.

Hi.

I assume you pasted in a raster image, which is no vector in any bit.
If so, and as you need it for cnc cutting, you would need to trace the image with the pen tool (Shift+F6).
http://en.wikipedia.org/wiki/Vector_graphics