Clean Bottom of Drilled Hole

I wrote this subroutine to solve a few issues I had when drilling a blind hole on my lathe then boring and wanting a clean (flat) bottom. If you just start at Z0 and bore outward on X the back side of your boring bar (usually 6 degrees) will hit the back side of the slope. And where do you start boring? This subroutine uses some trig to figure all that out for you.

You need to make sure your boring bar is less than 1/2 the hole diameter.

All you need to do is supply:
SFM
Feed
Max RPM
Hole Diameter
Z Bottom of the hole (to the drill point)
Z Clearance (how far to back bore when finished)
Drill Point Angle
Depth of Cut
Coolant

Here is a screen shot of the resulting back plot.



John