Newbie- Help with Arc centers i,j,k

[andy_trm]

hi,

would it be possible for someone to explain how the g02 & g03 codes work with I,J & K

I am unsure how these are calculated

thanks so much

[dcoupar]

I = X-axis arc center location
J = Y-axis arc center location
K = Z-axis arc center location

Depending on the control, I, J (and K) can either be the absolute coordinates of the arc center, or as in Fanuc, Yasnac, Haas, Mitsubishi, etc. I, J (and K) are the distance and direction from the start-point of the arc to the center.

[Perfect Circle]

Here is some info
Go to Page 235
CNC programming handbook: a ... - Google Books

[dcoupar]

Here's an example for Fanuc.

Note that you can also specify the radius using R instead of the arc-center. So either of the following would work:

G03 X-1.3991 Y-0.3897 I-0.5433 J-0.8792
-or-
G03 X-1.3991 Y-0.3897 R1.0336

There are a couple of limitations when using R:

1. If the arc is 180 degrees or less, specify R
2. If the arc is greater than 180 degress, specify R-
3. If it's a full circle, you must use I and/or J.