Re: [CAD_CAM_EDM_DRO] Drill roughing?

I use it a lot in manual milling. Done properly, a drill will remove
material 3X as fast as an endmill, even with the cleanup passes required.
If'n you're real clever, you can grind a chipbreaker groove on each of the
drill's cutting edges. It helps *not* to have them damn strings come up
and whipping around! Also, it is easier to sharpen the endmills that will
then get dull, only on the very bottom cutting edges... On a CNC, after
drilling a pilot hole, then to generate a profile, I've also used a plain
old G81 drilling G-Code, with an endmill, instead of drill, and indexed
about 0.050" (about 1% of cutter dia). Works great, if your post allows
looping, or incrementing "X" number of times, etc.

RayHex
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> From: Randy Gordon-Gilmore <zephyrus@...>
>
> Mastercam has a roughing technique that I don't remember seeing in
> hobby-scale CAM software. It drills out material. I've seen the
> machinists using that (pre-roughing?) in deep and/or narrow cavities.
>
> When would I use such a technique, what are the tradeoffs and is it
> somthing that is machine-dependent? I.e. would it be reasonable to try

on

> a Sherline CNC mill?