Re: [CAD_CAM_EDM_DRO] Re: Question about angular and linear feedrates

lets keep it simple
if the control dosent have a register for the A-axis diameter offset
it should at least be able to do an interpolation based on the user units
of both axes

in the example Dan gave I'm guessing the software did the position
interpolation right and the tool path was a smooth helix from
X0,A0 to X.5,A180 but for the velocity interpolation only used the X-axis
value and ignored the larger value of the A-axis movement and
forced the A-axis to move too fast

if the control does have an A-axis diameter offset it can use that
to calculate the feedrate but if it dosent or if that offset is set to zero
then the control should calculate the feedrate with the values its given

Brian

On Monday 05 August 2002 01:42, you wrote:
> What the control really requires is the relative position of the zero
> point to the centre of rotation of the A-axis so it can calculate the
> actual coordinates and distances travelled by the toolpoint for all
> subsequent movements.
> If the zero point is directly above the centre of rotation and almost
> touching the work surface of a cylynder then that of course is the
> radius. I've termed this Initial Tool Offset around A-axis (ITOA) to
> hopefully save confusion unless anyone has a better term.
> I assume that the zero point for 4-axis work is normally set at or
> above the centre of rotation of the A-axis. Is it likely that the
> zero point would ever be offset in the Y-axis ?
>