how to cut a drawing exactly in half?

Is this possible?

I am exploring making a tileable background using animate and to do this i need to be able to cut the image in half and rearrange.

Is there any mechanical way of doing this rather than eyeballing?

That is a pretty good idea. I will give it a go.

The only thing that I could suggest is to go in your drawing view and use Snap to Grid to align your drawing object to the drawing grid. Then you can use your Cutter tool with the Marquee straight down the centre of the grid.