I Broke My Only .1065" Drill Bit

I handcoded a .7" deep cut at particular X and Y and then again another X and Y and forgot to raise the Z axis above the workpiece first.  Of course it broke the drill bit.  This is such an easy oversight that I wrote a C program to produce the appropriate code instead.  Less opportunities to screw up.

I had to wait until new  .1065" drill bits arrived yesterday but this morning I was able to drill and tap all these holes.  There are parts that hold the slow motion control axis.  These are pillow blocks with .235" hole for the axis and 6-32 holes that hold those pillow blocks to the base plate.

How deep should I make those pilot holes for 6-32?  Just to be sure that I could get 1/2" of screw in the pillow blocks, I drilled the holes .7" deep.  The 6-32 tap has .5" of exposed cutting surface so that I knew when to stop.  When I turned the screws into the hole, I discovered that the screw tapped beyond the .5" of tapped thread.  CFC is very stiff with high tensile strength but it is not spectacularly hard.  Stainless steel screws once started will continue tapping quite well.