Hole in a Slope

Hello,

I am trying to use the hole wizard to create a hole in a slope but instead of normal to the surface, I need it to be perpendicular to the base. When I use the Smart Dims tool it gives me,





Sketch is open, self-intersecting, or intersects the centerline.

How do I make this and still have a fully defined feature?

Thanks in advance.

Georgie

SolidworksGeneral