Flash mx and line art

I am experimenting, albeit on a very basic level with line art, using the moveTo and lineTo commands. I have produced a fla for you all to see.

The problem I am having is that on four or five keyframes I have redrawn the lines to produce the desired effect. However I can’t seem to remove the lines from each previous key frame. Result: All the lines I have drawn appear rather than only the lines related to the keyframe.

Also I am sure there is an easier way of accomplishing this effect. I guess I am prompting a discussion of when tweening is appropriate. I am trying to use Actionscript for everything in flash, is this wrong?

Any ideas on any of the above would be great

cheers

the clear() command will erase all previously drawn imagery on the screen. Just put it before all your other commands on each frame.