To create the zig-zag pattern, I create a polyline along one edge of the part
Then I use the Array tool to copy it
Then to connect the ends I create a circle & chop it in half
Line it up with the first 2 polylines, then use array again to copy to all the lines
Now copy/paste or dupicate those, rotate 180 or mirror horizontally, and move to the bottom
Delete the extra arc, and the join all the vectors.