On Thu, 07 Mar 2013 16:58:09 -0500, Rich Webb wrote:

Ding it with a punch to get started, else you'll just skip around on
that convex surface.

I didn't get any further than the punch mark with the titanium
coated drill bit, even after 10 minutes of trying:
http://www4.picturepush.com/photo/a/...g/12362162.jpg