Re: [CAD_CAM_EDM_DRO] xyij

"Derek B." wrote:

> Hi all
> What does I and J actually stand for in the g-code. I have been
> trying to figure this out using a plot view. My g-code program does
> not
> have K.

To move in an arc, you need to pre-select the arc plane (XY is a G17,
for instance), then
you specify the endpoint wih X and Y (the start point is where you are
before the command)
and you need to specify where the center of the arc is. You can specify
that with the
R word for radius, or use the I,J and/or K words to specify the distance
from current
position to the center. For instance, in the XY plane, I indicates
distance in the X
axis, J is for the Y axis. So, IJK corresponds to relative distance in
XYZ, respectively.
Now, some systems need IJK to be specified in absolute units, in other
words never
having a minus sign. many others require IJK to have the correct sign,
as
I = (current X coordinate) - (arc center X coord.)

K will only work if a G18 or G19 command has been given, on machines
with
in-plane arcs. G18 specifies ZX plane, and G19 is YZ plane. There are
some
controls that can interpolate 3-D arcs, but I've never gotten into that.

Jon