Tooling suggestions for titanium

Hey guys. I am going to be needing to countersink some holes in titanium. They are sized for #4 or #6 hardware if I remember correctly. Either way, can someone give me some suggestions for tooling material and coatings? I know I need 82° as metric is 90 and 100 is used for aviation. Just not sure on material and coatings for it.

I will be doing 6 holes per piece and chances are it will be no more than 10 pieces. The actual process will be done using a friends bridgeport.

Thanks in advance for any help in this.