I am interested in the drilling parameters used for 10 mil drill bits when 
drilling PCMCIA printed circuit boards. The other factors that would be 
important are stack height, material thickness, copper and dielectric 
thickness as well as number of layers, etc.

To make an easy to understand example, consider a 6 layer board with half 
ounce copper inside that is 16 mils thick with 20 mil pads.  What stack 
height, feed and speed would you use? How many drill bits would you expect to 
break during one table load with 5 heads, and what length flute would you use? 
What would be your preference as to retract rate and dwell time? How far would 
you go into the backup?  What Brand do you prefer for backup and entry 
materials and do you use entry material? What kind of drill splay would you 
expect on the bottom panel?

Did I say this was an easy to understand example?   



SRT