Messages

1

General Mach Discussion / Re: G12 not moving Y axis, sometimes.

« on: October 14, 2014, 04:59:38 PM »

Yes, that fixes it. I checked my configuration and I see that IJ absolute mode is selected in the general configuration screen, so G91.1 obviously overrides that and changes to incremental mode. Also G90.1 executed any time after G91.1 breaks it again, as you might expect. Interesting though that in IJ absolute mode for some Y coordinates and G12 I values, G12 works yet for others it doesn't. The inconsistencies for different Y coordinates, I values, and between G12 and G13 are rather suspicious, particularly since the G-Codes documentation indicates that G90.1 and G91.1 should only affect G02 and G03.

2

General Mach Discussion / Re: G12 not moving Y axis, sometimes.

« on: October 14, 2014, 03:59:08 AM »

Ok, thanks. Here it is.

3

General Mach Discussion / Re: G12 not moving Y axis, sometimes.

« on: October 13, 2014, 07:26:27 PM »

I would like to open up this issue for discussion again. Recently I have been trying to do some milling operations to create round holes of diameters not available in common drill bit sizes. I'm using the latest version of Mach3 (R3.043.066). G12 is the operation of choice but I am experiencing the same problem as described in the original post on this topic. The problem occurs with various combinations of X and Y coordinates and hole radius (G12 I parameter) but not with very small variations of the parameters. G13 always seems to work correctly for any parameters. Would anyone care to try the following simple G code as one example to see what happens? This can be done quickly from the standard MDI screen Input entry box. No specific hardware is involved, I'm doing it in off-line mode to debug and simulate code before moving to the actual CNC mill. Just watch the X and Y position displays to see the results.

1. Correctly moves the Y axis:
G0 X5.2432 Y1.4525
G12 I.127

2. Fails to move the Y axis:
G0 X5.2432 Y1.4526
G12 I.127

3. Correctly moves the Y axis:
G0 X5.2432 Y1.4526
G13 I.127

As you can see the only difference is 0.0001 for the Y coordinate, but the behavior is quite a bit different for G12. The same parameters work correctly for G13. It looks to me like a high probability of a bug in G12.