Re: Cutter compensation

Cutter radius compensation is such a powerful feature that IMO any
control that doesn't support it would be deficient for general
machining.

In my experience with cutter comp on different machines, it's so
control-dependant it's difficult to generalize about how the lead-in
to the radius offset works. I know of one machine that allows CC to
be invoked in a rapid move (G00) to position, that's nice. Another
machine requires CC to be turned off in a linear move (G01) prior to
turning it on in the next linear move. That machine also does the
radius offset in rapid as the first action of the linear move
invoking CC (which equals broken end mill if the the cutter is in
the workpiece while invoking CC).

The 5 x 5 box of the original poster could be done on most
commercial machines using a canned pocketing cycle which would
automatically handle the CC. The entire toolpath could be specified
in one instruction. This is a good example of why an assortment of
canned cycles are always included as part of a full featured control.

Doug

--- In CAD_CAM_EDM_DRO@yahoogroups.com, bjammin@i... wrote:
> At 07:20 PM 1/5/03 -0600, you wrote:
> >Generally, you must feed a distance of at least
> >the cutter comp distance to effect it.
>
> Nope, the cutter will move appropriately even if less distance
than the
> comp. This may be control-dependant, but all of them I've used
will do it.
>
> >Also, it's
> >best not to start a cut in a corner (actually, forbidden in
> >some software).
>
> I've always started comp at corners and never had it forbidden.
You will
> often have a mar or blem if you cut first from a point on a line
and then
> back to it.
>
> Regards, Hoyt McKagen
>
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