Arc center mode question

I have been using EMC2 with Cambam to generate gcode. Some programs run fine others don't like the arc center mode. Is there a way to change "Absolute" to "Incremental" and back? Please speak slowly I have only been at this for a couple weeks. LOL thanks Carl

Hi Cwebs,
I'm not terribly familiar with Cambam- so this may be of limited use.. Invoking G90 puts EMC in absolute mode, and G91 puts EMC in incremental mode. These can be typed into MDI...


G90 (absolute mode) clockwise arc, pretending that the machine is at x1, y1, ending coordinate is x1, y2, arc center x1, y1.5, arc diameter is 1 unit:

G90 G17 (sets absolute mode and the arc to be on x/y plane)
G2 X1 Y2 I1 J1.5 (g2= clockwise arc, x1 = ending x position, y2 = ending y position, i1 = x-axis arc-center coordinate, j1.5 = y-axis arc-center coordinate)

G91 (incremental mode) clockwise arc, starting position doesn't matter:

G91 G17 (sets incremental mode and the arc to be on the x/y plane)
G2 X0 Y1 I0 J.5 (g2 = clockwise arc, x0 = ending difference of x position, y1 = ending difference of y position, i0 = x axis arc-center offset, j.5 = y-axis arc-center offset)


Hope that helps a little.

Robin

That helps to know I can set the arc circle in the gcode. I thought I had to change it in Axis. I use Cambam and Mach to check my gcode in my Windows computer and then put the code on memory stick and run downstairs to put it in the CNC computer. In Mach I just changed the setup in options. Thought I would have to do the same in EMC. Thanks Carl