Extruding along a path
 

I'm trying to create a NURB expand along a circular path in an animation. So that it starts small and expands to complete a circle.

I don't want the circle to be filled in the center, just the rim of it.

What might be a good way to do this.

okay.. I figured out how to extrude it along the path. But now I can't key frame different lengths to create an animation. is there any way to make it look like its growing along the path?

In your extrude options, use a Partial Curve Range. You then get two additional attributes in your channel box that allow the extrude to animate along the path.

Hey thanks Mike. :)

However, I have another question about extruding. :(

I'm trying to extrude a circle along a path to create a tube, but the size keeps shrinking. Why is this happening? And how can i Fix? I've tried changing the scale, but it keeps making the same size.

Thanks for any help. :)