Re: Dumb question on the drilling of holes

Alan,

Use a spotting drill. Center drills are not good for spotting, too
much likelyhood of breaking the tip off in the workpiece especially
on imperfect drilling surfaces.

If you don't want to go to the trouble of spotting the holes then use
drill bits with points suitable for self starting. The most common
of these is the 135 degree split point. Other proprietary drill
points work well too, like the Winslow point and others of that type.

Doug

--- In CAD_CAM_EDM_DRO@y..., alan@s... wrote:
> Forgive me this seemingly dumb question, but how does a
person "drill"
> accurately placed holes under CNC control without first center-
punching
> them.
>
> I currently use a center drill to start the hole ( for deep holes )
or
> just mill the hole via G02/03 command for shallow ones.
>
> But it occurs to me that there's got to be a better way.
Are "spotting
> drills" that better way ?
>
> Thanks in advance for any thoughts.
>
> Alan
>
> --
>
> Alan Rothenbush | The Spartans do not ask the number
of the
> Academic Computing Services | enemy, only where they are.
> Simon Fraser University |
> Burnaby, B.C., Canada | Agix of
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